# com.calcfleet/calculators

> Tested financial & practical calculators as free, no-auth MCP tools for AI agents.

- name: com.calcfleet/calculators
- version: 1.0.0
- connection class: R0 (autonomous)
- trust: 76/100 flags: no-repository
- quality: 76/100 (good)
- owner: not claimed
- descriptor: https://api.protogrid.dev/v1/servers/com.calcfleet%2Fcalculators
- tools: https://api.protogrid.dev/v1/servers/com.calcfleet%2Fcalculators/tools

**An agent can connect right now, no human step.** Remote endpoint, no authentication, reachable on the last probe.

## Connection (mcpServers)

```json
{
  "mcpServers": {
    "calculators": {
      "type": "http",
      "url": "https://calcfleet.com/api/mcp"
    }
  }
}
```


## Trust

- hygiene: 80
- liveness: 100
- freshness: 65
- provenance: 55
- drivers: +dns-namespace +website +reachable +uptime-100% ~updated-107d-ago -no-repository
- Derived from observable signals (official registry feed and our own credential-free probes); no code audit performed.

## Quality 76/100 (good)

### protocol: 75 (weight 25)

- warn `protocol.modern`: newest supported version is 2025-11-25; 2026-07-28 not supported, older versions are deprecated until 2027-07-28
- n/a `protocol.stateless`: only applies to 2026-07-28 servers
- pass `protocol.transport`: streamable HTTP
- n/a `protocol.list_ttl`: only applies to 2026-07-28 servers

### authorization: n/a (weight 15)

- n/a `auth.prm`, `auth.as_metadata`, `auth.cimd`: no remote uses OAuth
- n/a `auth.secret_in_url`: no templated URL

### tool hygiene: 64 (weight 30)

- pass `tools.descriptions`: every tool has a description
- pass `tools.description_length`: descriptions are concise
- pass `tools.schemas`: every tool has an object input schema
- fail `tools.annotations`: no tool declares readOnlyHint or destructiveHint, so clients cannot tell safe calls from risky ones
- fail `tools.directory_hints`: no tool declares all four of readOnlyHint, destructiveHint, idempotentHint and openWorldHint; missing: calories_burned_calculator (readOnlyHint, destructiveHint, idempotentHint, openWorldHint); debt_payoff_calculator (readOnlyHint, destructiveHint, idempotentHint, openWorldHint); payback_period_calculator (readOnlyHint, destructiveHint, idempotentHint, openWorldHint); …
- warn `tools.token_cost`: about 22,316 tokens to load every tool
- pass `tools.api_dump`: tools are not a one-to-one API dump

### stability: 100 (weight 15)

- pass `stability.changes`: no tool changes in 30 days
- pass `stability.rug_pull`: no tool changed its meaning under the same name

### dependencies: n/a (weight 15)

- n/a `deps.known_vulns`, `deps.mcp_sdk_version`, `deps.resolvable`: no npm or PyPI package

- tools: 122, about 22,316 tokens to load them all
- tool set hash: a9b5cd96a7972768fb8d81e559750125
- badge: [![protogrid quality](https://protogrid.dev/badge/com.calcfleet/calculators.svg)](https://protogrid.dev/servers/com.calcfleet/calculators)
- Checks run on what our credential-free, read-only probes observe; tools are never called and no code audit is performed.

### Tool changes

_No tool definition changes recorded._

## Remotes

- https://calcfleet.com/api/mcp (streamable-http, auth none, reachable true, uptime30d 1)

## Packages

_none_

## Tools (122)

- `401k_match_calculator`: 401(k) Employer Match Calculator — Calculate your 401(k) employer match: enter salary and contribution rate to see the free money you earn, your total yearly savings, and long-run growth.
- `ai_agent_cost_calculator`: AI Agent Cost Calculator — See what an AI agent really costs per successful task: steps, tokens, model pricing and success rate turn dashboard cost per run into the true unit cost.
- `ai_automation_payback_calculator`: AI Automation Payback Calculator (Process ROI) — Estimate the payback of automating a process with AI: task volume, time saved, review effort, and API costs give net monthly savings and break-even months.
- `ai_build_vs_buy_calculator`: AI Build vs Buy Calculator (API vs Self-Host) — Compare the monthly cost of a hosted LLM API against self-hosting on your own GPUs. Find the break-even token volume and see which option is cheaper for you.
- `ai_job_exposure_calculator`: AI Job Exposure Score — An AI job exposure score built from published research (Eloundou et al. 2023, O*NET, Goldman Sachs): estimate your task mix, not a prediction about you.
- `ai_roi_calculator`: AI Tool ROI Calculator (Payback on Adoption) — Estimate the ROI and payback of an AI tool: enter hours saved per week, staff count, and cost to see monthly net savings, break-even months, and annual return.
- `amazon_fba_calculator`: Amazon FBA Profit Calculator — Calculate Amazon FBA net profit, margin, and ROI for any product. Enter price, COGS, and size tier to see the full fee breakdown and your break-even price.
- `apy_calculator`: APY Calculator: APR to APY Conversion — Convert your nominal rate (APR) to APY instantly. See how compounding frequency—daily, monthly, or quarterly—affects your true annual yield and final balance.
- `aquarium_stocking_calculator`: Aquarium Volume & Stocking Calculator — Work out your fish tank volume and stocking capacity. Enter length, width, and height in inches to get gallons, litres, inch-of-fish, and heater wattage.
- `aspect_ratio_calculator`: Aspect Ratio Calculator (Resize & Crop) — Simplify an aspect ratio and resize while keeping it. Enter width and height to get the ratio like 16:9, then a new width to solve the matching height.
- `baking_pan_conversion_calculator`: Baking Pan Size Conversion Calculator — Convert a recipe between round, square, and rectangular baking pans. Scale batter by pan area, not diameter, to see the exact ratio and bake-time guidance.
- `balance_transfer_calculator`: Balance Transfer Calculator — See how much a 0% balance transfer saves vs staying on your current APR. Enter the fee, promo months, and planned payment to find out if it is worth it.
- `body_fat_calculator`: Body Fat Percentage Calculator (Navy Method) — Estimate your body fat percentage with the US Navy tape-measure method. Enter your sex, height, neck, waist, and hip to see body fat and lean body mass.
- `break_even_calculator`: Break-Even Point Calculator — Calculate your break-even point in units and revenue. Enter fixed costs, variable cost per unit, and price to see exactly when your business turns profitable.
- `brine_calculator`: Brine Calculator (Salt Ratio by Weight) — Calculate salt and sugar for wet or dry brines by weight: enter water volume or meat weight and a salt percentage to get exact grams and a strength chart.
- `burn_rate_runway_calculator`: Burn Rate & Runway Calculator — Calculate startup burn rate and cash runway. Gross vs net burn, default alive or dead verdict, and month-by-month cash balance simulation with revenue growth.
- `cac_ltv_calculator`: CAC : LTV Ratio Calculator — Calculate Customer Lifetime Value, LTV:CAC ratio with poor/fair/good/excellent verdict bands, CAC payback months, and monthly gross profit per customer.
- `calorie_deficit_calculator`: Calorie Deficit Calculator (Goal Weight by Date) — Set a goal weight and a target date to see the daily calorie deficit you need, your projected weekly loss rate, and whether the pace is safe or too fast.
- `calories_burned_calculator`: Calories Burned Calculator (MET-Based) — Calculate calories burned by activity with the MET formula: enter weight, minutes, and activity to estimate energy spent, and compare exercises side by side.
- `car_affordability_calculator`: Car Affordability Calculator — How much car can you afford? Enter your monthly budget, APR, loan term, and down payment to see your max loan and car price, plus a 15%-of-income rule check.
- `car_depreciation_calculator`: Car Depreciation Calculator — Estimate what your car will be worth in the years ahead. Enter price and depreciation rates to see a year-by-year value curve, total loss, and percent lost.
- `car_lease_calculator`: Car Lease Payment Calculator (Money Factor) — Estimate your monthly car lease payment from the cap cost, residual, term, and money factor. See the depreciation and finance split, sales tax, and APR.
- `car_loan_calculator`: Car Loan Calculator with Sales Tax and Trade-In — Calculate your exact monthly car payment including sales tax and trade-in. View your full amortization schedule, total interest paid, and cost of ownership.
- `cd_ladder_calculator`: CD Ladder Calculator — Build a CD ladder: split your savings across staggered-maturity CDs and see year-one interest, per-rung breakdown, and your blended APY across the whole ladder.
- `churn_rate_calculator`: Churn & Retention Rate Calculator — Calculate monthly and annual customer churn, revenue churn, and net revenue retention. Compounding conversion and implied average customer lifetime included.
- `closing_cost_calculator`: Mortgage Closing Cost Estimator — Estimate US mortgage closing costs before you buy. See itemized origination, appraisal, title, and prepaid fees with typical ranges and cash to close.
- `coast_fire_calculator`: Coast FIRE Calculator — Find your Coast FIRE number: the amount you need invested today so it grows to your FIRE target by retirement with zero further contributions. Mind the gap.
- `compound_interest_calculator`: Compound Interest Calculator — Calculate compound interest with monthly contributions. See your balance grow year by year and discover exactly how much of your final balance is pure interest. Supports Verifiable Calculation Certificates: pass certify=true to also receive a signed, independently verifiable receipt (DSSE/Ed25519) for this exact calculation.
- `concrete_calculator`: Concrete Calculator (Cubic Yards & Bags) — Calculate how much concrete you need for a slab, footing, or pad. Enter length, width, and thickness to get cubic yards, cubic feet, and the exact bag count.
- `contractor_vs_employee_calculator`: 1099 vs W-2 Rate Calculator — Compare a W-2 job to 1099 contract work: enter salary, employer FICA, benefits, and PTO to see the equivalent 1099 gross rate you need to break even fairly.
- `cost_per_mile_calculator`: Cost Per Mile to Own a Car Calculator — See what your car truly costs to drive: enter yearly fuel, maintenance, insurance, depreciation, and financing interest or lease cost to get your real cost per mile driven.
- `credit_card_payoff_calculator`: Credit Card Payoff Calculator — Find out how many months until your credit card is paid off — and how the minimum-payment trap costs you decades and multiples of your original balance.
- `crop_factor_calculator`: Crop Factor / Equivalent Focal Length Calculator — Convert focal length to a full-frame equivalent by crop factor. Enter focal length, aperture, and sensor to get equivalent focal, aperture, and field of view.
- `debt_consolidation_calculator`: Debt Consolidation Calculator — See how your current debts compare against one new consolidation loan. A lower rate with a longer term can still cost you more — see the true lifetime numbers.
- `debt_payoff_calculator`: Debt Payoff Calculator: Avalanche vs Snowball — Compare the avalanche and snowball debt payoff strategies side by side. See how much interest you save and how many months sooner you'll be debt-free.
- `deck_boards_calculator`: Deck Board Calculator (Linear Feet & Boards) — Calculate how many deck boards you need. Enter deck length, width, board width, gap, and board length to get area, linear feet, board count, and total cost.
- `depth_of_field_calculator`: Depth of Field & Hyperfocal Calculator — Calculate depth of field and hyperfocal distance from focal length, aperture, and subject distance. See the near and far limits of sharp focus in meters.
- `dividend_reinvestment_calculator`: DRIP Dividend Reinvestment Calculator — See how reinvested dividends compound your portfolio. Enter dividend yield, price growth, and yearly contributions to project future value and total growth.
- `dog_age_calculator`: Dog Age Calculator (Human Years, Size-Adjusted) — Convert your dog age into human years the AKC way, adjusted for body size — not the old myth of multiplying by seven. Enter age and size for a real estimate.
- `down_payment_calculator`: Down Payment Calculator with PMI Threshold — Calculate your down payment amount, loan size, and PMI status instantly. See the dollar gap to 20% equity and compare multiple down payment scenarios.
- `drywall_calculator`: Drywall Sheet Calculator — Calculate how many drywall sheets you need for a room. Enter total wall and ceiling area, waste percent, and sheet size to get sheets, screws, mud, and tape.
- `dti_calculator`: Debt-to-Income (DTI) Ratio Calculator — Calculate your front-end and back-end debt-to-income ratio instantly. See how your debt load compares against the 36%, 43% QM, and 50% lender thresholds.
- `ecommerce_profit_margin_calculator`: Ecommerce Profit Margin Calculator — Calculate your true ecommerce profit margin including COGS, shipping, packaging, payment fees, and ad spend per unit. See contribution vs fully-loaded margin.
- `electricity_cost_calculator`: Appliance Electricity Cost Calculator — Work out what any appliance really costs to run. Enter its watts, hours per day, and your kWh rate to see the cost per day, month, and year at a glance.
- `employee_cost_calculator`: True Cost of an Employee Calculator — Calculate the true, fully loaded cost of an employee beyond base salary: add employer FICA, benefits, and overhead to see the total and its multiple of pay.
- `etsy_fee_calculator`: Etsy Fee & Profit Calculator — Calculate Etsy fees, net proceeds, and break-even price for any listing. Fee breakdown always visible: listing $0.20, transaction 6.5%, payment 3%+$0.25.
- `ev_charging_cost_calculator`: EV Charging Cost Calculator — See what it really costs to charge your EV at home or on public chargers. Enter battery size, charge window, and rates for cost per charge and per mile.
- `fence_calculator`: Fence Calculator (Posts, Panels, Rails) — Calculate fence materials fast: enter your run length, post spacing, and picket width to get exact posts, rails, and pickets, plus an optional total cost.
- `fertilizer_calculator`: Fertilizer Calculator (N-P-K Rate) — Work out how much fertilizer to spread: enter your lawn size, target nitrogen rate, and the bag N number to get pounds of product per feeding and per season.
- `fine_tuning_cost_calculator`: Fine-Tuning Cost Calculator — Estimate what a fine-tuning run costs: GPU-hours for a self-managed cluster versus per-token managed API pricing, with wall-clock time and the cheaper path.
- `fire_calculator`: FIRE Calculator: When Can You Retire Early? — Calculate your FIRE number and years to early retirement. Enter current savings, annual expenses, and expected return rate to reach financial independence.
- `flooring_calculator`: Flooring Calculator (Boxes & Cost) — Figure out how many boxes of flooring to buy and what it costs. Enter room length, width, waste percentage, box coverage, and price per box for an estimate.
- `freelance_hourly_rate_calculator`: Freelance Hourly Rate Calculator — Calculate your freelance hourly rate accounting for taxes, business expenses, and a profit margin. Find out exactly what to charge to hit your income goal.
- `gas_vs_electric_car_calculator`: Gas vs Electric Car Cost Calculator — Compare the yearly fuel cost of a gas car versus an electric car. Enter miles, MPG, and rates to see annual savings, break-even years, and 5-year totals.
- `global_hiring_cost_calculator`: Global Hiring Cost Calculator — Compare the annual cost of a US W-2 employee against an international contractor or an EOR hire, including employer taxes, benefits, and platform fees.
- `gpu_vram_calculator`: GPU VRAM Calculator (Model Size & GPU Fit) — Calculate the VRAM a large language model needs by parameter count and precision (fp16, int8, int4), then see which GPU it fits — from RTX 4090 to H100.
- `grass_seed_calculator`: Grass Seed Calculator — Calculate how much grass seed you need: enter your lawn area in square feet and the seeding rate to get pounds required and bags to buy for new or overseed.
- `gravel_calculator`: Gravel & Aggregate Calculator (Yards & Tons) — Calculate how much gravel or aggregate you need for a driveway, path, or garden bed. Enter area and depth to get cubic yards, cubic feet, and tons by density.
- `heart_rate_zone_calculator`: Heart Rate Zone Calculator — Calculate your five heart rate training zones from your age using the 220 − age or Tanaka formula, with an optional Karvonen resting heart rate refinement.
- `heat_pump_savings_calculator`: Heat Pump vs Furnace Savings Calculator — Compare a heat pump against electric resistance or a furnace. Enter your heating need, COP, and rate to see yearly running cost, savings, and payback.
- `heloc_calculator`: HELOC Payment Calculator (Draw + Repayment) — Calculate your HELOC draw and repayment payments. See the payment shock when interest-only switches to fully amortized, plus total interest across both phases.
- `hire_vs_outsource_calculator`: Hire vs Outsource Calculator — Compare the fully loaded cost of an in-house hire against outsourcing to an agency or freelancer, with a break-even hours line showing when hiring wins.
- `home_affordability_calculator`: Home Affordability Calculator — Find out how much house you can afford using the 28/36 DTI rule. Enter income, rate, and debts to get your max loan, price, and a DTI scenarios table. Supports Verifiable Calculation Certificates: pass certify=true to also receive a signed, independently verifiable receipt (DSSE/Ed25519) for this exact calculation.
- `home_battery_size_calculator`: Home Battery Backup Size Calculator — Size a home backup battery. Enter your essential load in kW and hours of backup to get the kWh needed, how many battery units, and runtime at each load.
- `ideal_weight_calculator`: Ideal Weight Calculator (4 Formulas) — Estimate ideal body weight from your height and sex using four classic formulas (Devine, Robinson, Miller, Hamwi) and see the healthy range, not one number.
- `lead_gen_budget_calculator`: Lead Gen Budget Calculator — Work out your lead generation budget: leads needed for a customer goal, the implied CAC against your LTV target, and the maximum cost per lead to pay.
- `lease_vs_buy_car_calculator`: Lease vs Buy a Car Calculator — Compare leasing versus buying a car over the same time horizon. See each total cost, the difference, and true net cost per month once resale value is counted.
- `llc_vs_sole_proprietor_calculator`: LLC vs Sole Proprietor Calculator — Compare a sole proprietorship with an LLC: formation and annual state costs, self-employment tax on both, and the estimated savings of an S-corp election.
- `llm_api_cost_calculator`: LLM API Cost Calculator (GPT-4o, Claude, Gemini) — Estimate monthly API costs for GPT-4o, Claude, and Gemini from tokens per request and volume. See input vs output cost split. Prices as of 2025 — verify.
- `llm_self_host_vs_api_calculator`: LLM Self-Host vs API Cost Calculator — Find the monthly token volume where self-hosting an LLM on rented GPUs beats paying per token for an API. Compare costs, GPUs needed, and breakeven point.
- `llm_throughput_calculator`: LLM Throughput & GPU Sizing Calculator — Estimate how many GPUs your LLM needs: concurrent users and target tokens per second become cluster size, monthly cloud cost, and real utilization at load.
- `loan_amortization_calculator`: Loan Amortization Calculator — Get your full loan amortization schedule instantly. See how each payment splits between interest and principal, and how extra payments cut total interest paid.
- `macro_calculator`: Macro Calculator: Protein, Carbs and Fat Targets — Calculate your daily protein, carb, and fat targets from your calorie goal. Choose a preset split or customize macros for your fitness or body-composition plan.
- `margin_markup_calculator`: Margin and Markup Calculator — Calculate gross profit, margin percentage, and markup percentage instantly. Enter cost and price to see the right number for your business pricing strategy.
- `mortgage_overpayment_calculator`: Mortgage Overpayment Calculator — See exactly how much interest and time you save by overpaying your mortgage. Instant amortization schedule plus a clear breakdown of the months you save.
- `mortgage_piti_calculator`: Mortgage PITI Calculator — Calculate your full monthly PITI mortgage payment—principal, interest, property taxes, homeowners insurance, and PMI. Full amortization schedule included.
- `mortgage_points_calculator`: Mortgage Discount Points Break-Even Calculator — Find out if buying mortgage discount points is worth it. See the break-even month and net gain over your planned hold period. Points lose if you sell early.
- `mortgage_refinance_calculator`: Mortgage Refinance Calculator — Find out if refinancing your mortgage is worth it. Compare monthly payments, see when you break even, and spot if a lower rate actually costs more overall.
- `mulch_calculator`: Mulch Calculator (Cubic Yards & Bags) — Calculate how much mulch you need for a garden bed or landscape. Enter area and depth to get cubic yards, cubic feet, and the exact number of bags to buy.
- `one_rep_max_calculator`: One Rep Max (1RM) Calculator — Estimate your one-rep max from any set using the Epley and Brzycki formulas, then read a full percentage-of-1RM table to set training loads for every lift.
- `overtime_pay_calculator`: Overtime Pay Calculator (Time-and-a-Half) — Calculate overtime pay at time-and-a-half or a custom rate. Enter your hourly wage plus regular, overtime, and double-time hours for weekly and annual gross.
- `paint_calculator`: Paint Calculator: How Much Paint Do I Need? — Calculate exactly how much paint you need for any room. Enter room dimensions, number of coats, doors, windows, and paint coverage to get total liters and cans.
- `payback_period_calculator`: CAC Payback Period Calculator — Calculate your CAC payback period with simple and discounted methods. Find the month your customer acquisition cost is fully recovered, plus a cumulative chart.
- `pay_raise_calculator`: Pay Raise Calculator — Calculate your pay raise two ways: the nominal percentage increase and the real, inflation-adjusted raise, plus the annual and per-paycheck dollar gain.
- `personal_loan_calculator`: Personal Loan Calculator with APR & Amortization — Calculate your personal loan monthly payment, total interest, and true effective APR including any origination fee. Full amortization schedule included. Supports Verifiable Calculation Certificates: pass certify=true to also receive a signed, independently verifiable receipt (DSSE/Ed25519) for this exact calculation.
- `pet_cost_calculator`: Pet Cost Calculator (First-Year & Lifetime) — Add up the true cost of a pet: first-year and lifetime. Enter monthly food, vet, insurance, and supplies plus setup cost to see what it really adds up to.
- `pet_food_portion_calculator`: Dog & Cat Food Portion Calculator — Estimate how much to feed a dog or cat from ideal weight and activity using the vet RER formula. Enter weight and food calories to get daily cups to serve.
- `pizza_dough_calculator`: Pizza Dough Calculator (Baker's Percentage) — Calculate pizza dough by baker's percentage: enter ball count, weight, and hydration to get exact flour, water, salt, and yeast weights for your batch.
- `pricing_strategy_calculator`: Pricing Strategy Calculator — Model a price change before you commit: see the maximum volume you can lose and stay profitable, plus predicted demand and profit at a chosen elasticity.
- `print_resolution_calculator`: Print Resolution & Max Print Size Calculator — Find the largest quality print from your photo pixels, or the DPI a chosen print size lands at. Enter pixel size and a target size or DPI to check the fit.
- `product_pricing_calculator`: Product Pricing Calculator — Set the right selling price for your product. Enter fully-loaded unit cost — materials, labor, overhead, and platform fees — then choose a target margin.
- `prompt_caching_savings_calculator`: Prompt Caching Savings Calculator (LLM API Costs) — Estimate how much prompt caching cuts your LLM API bill: monthly input tokens, cacheable share, and hit rate give per-model savings, cache writes included.
- `pto_accrual_calculator`: PTO Accrual Calculator — Calculate how much paid time off you accrue each pay period from your annual PTO days, then project your future balance by pay date after the hours you've used.
- `puppy_weight_calculator`: Puppy Adult Weight Predictor — Predict your puppy adult weight from its current weight and age in weeks, with a size-class note. Enter the numbers to see the grown-up size to expect.
- `purchase_impact_calculator`: Purchase Impact Calculator — See the true cost of any purchase: what the price would grow to if invested, how many days of work it represents, and how far it pushes back your FIRE date.
- `rag_cost_calculator`: RAG Cost Calculator — Estimate what a RAG pipeline costs: one-time corpus embedding, monthly vector storage, and per-query LLM generation from verified 2026 provider prices.
- `recipe_cost_calculator`: Recipe Cost & Cost-Per-Serving Calculator — Cost out any recipe in seconds: enter ingredients, quantities, and unit prices to get total cost, cost per serving, and a suggested menu price by food cost.
- `recipe_scaler_calculator`: Recipe Scaler / Serving Size Calculator — Scale any recipe up or down: enter the original and desired servings, and this tool multiplies every ingredient by the exact ratio so amounts stay balanced.
- `rent_affordability_calculator`: Rent Affordability Calculator — Find out how much rent you can afford using the 30% rule, 50/30/20 budget, and a cashflow stress test. All three caps side by side so you see the trade-offs.
- `rent_vs_buy_calculator`: Rent vs Buy Calculator — Compare renting vs buying over any timeline. See which builds more wealth, when break-even hits, and how appreciation and rent increases tip the balance.
- `required_savings_calculator`: Required Savings Calculator — Find the monthly savings needed to reach a goal: three deterministic return scenarios plus an inverse Monte Carlo rate sized for your chosen success odds.
- `retirement_monte_carlo_calculator`: Retirement Monte Carlo Calculator — Estimate your retirement plan's success probability with 5,000 simulated Monte Carlo market paths, plus a fan chart of percentile balances at every age.
- `roas_calculator`: ROAS & Break-Even ROAS Calculator — Calculate ROAS and break-even ROAS instantly. Enter revenue, ad spend, and gross margin to see if your campaign is truly profitable — or just spending to spend.
- `roi_calculator`: ROI Calculator with Annualized Return — Calculate ROI and annualized return on any investment. Add fees and costs to see true net gain and the real annual growth rate behind the headline number.
- `roth_ira_calculator`: Roth IRA Growth Calculator — See how a Roth IRA grows tax-free. Enter your annual contribution, expected return, and time horizon to project future value, total paid in, and growth.
- `running_pace_calculator`: Running Pace Calculator with Race Predictions — Calculate your per-km and per-mile running pace from any distance and time. Get predicted finish times for 5K, 10K, half marathon, and marathon, plus splits.
- `saas_mrr_growth_calculator`: SaaS MRR Growth Projection Calculator — Model SaaS MRR growth with monthly compounding: add new revenue, subtract churn, apply expansion. See projected ARR and months to any revenue milestone.
- `salary_to_hourly_calculator`: Salary to Hourly Calculator (and Back) — Convert an annual salary to an hourly wage or an hourly rate back to a yearly salary. Set your hours and weeks to see weekly, biweekly, and monthly pay too.
- `sales_tax_calculator`: US Sales Tax Calculator (by State) + Reverse — Calculate US sales tax by state. Add or strip tax from any price. Select a state to prefill the rate; all 50 states included. 2025 base rates — local rates vary
- `savings_drawdown_calculator`: Savings Drawdown Calculator — See how long your savings will last: enter your balance, monthly withdrawal, and expected return to find the months and years until the money runs out.
- `savings_goal_calculator`: Savings Goal Calculator — Calculate the monthly savings you need to reach any goal. Input your target, current balance, annual rate, and years to see your required monthly contribution.
- `solar_panel_savings_calculator`: Solar Panel Savings Calculator — Estimate how much a rooftop solar system saves on your power bill: enter size, sun hours, cost, and any currently applicable credit to see yearly savings and payback.
- `solar_system_size_calculator`: Solar System Size Calculator (kW Needed) — Find the solar system size you need: enter yearly kWh usage, peak sun hours, and panel wattage to get the required kW and the number of panels it takes.
- `student_loan_calculator`: Student Loan Payoff Calculator — See exactly how many months until you pay off your student loans, how much extra payments save in interest, and whether refinancing makes financial sense.
- `take_home_pay_calculator`: Take-Home Pay Calculator (US) — Estimate your US take-home pay for 2026. Enter gross salary and filing status to see federal income tax, Social Security, Medicare, and monthly net income.
- `tdee_calculator`: TDEE Calculator: Daily Calorie Needs — Calculate your Total Daily Energy Expenditure (TDEE) using the Mifflin-St Jeor formula. Find your daily calorie needs for fat loss, maintenance, or muscle gain.
- `tiered_commission_calculator`: Tiered Commission Calculator (USD) — Calculate tiered sales commission in USD: a base rate up to a threshold, a higher rate above it, plus any settlement adjustment. See the exact per-tier math. Supports Verifiable Calculation Certificates: pass certify=true to also receive a signed, independently verifiable receipt (DSSE/Ed25519) for this exact calculation.
- `tile_calculator`: Tile Calculator (Tiles Needed) — Calculate how many floor or wall tiles you need. Enter room size, tile dimensions, and waste percentage to get total tiles, boxes to buy, and material cost.
- `time_lapse_calculator`: Time-Lapse Calculator (Interval, Clip, Storage) — Plan a time-lapse: enter shoot length, shot interval, playback fps, and file size to see how many frames you shoot, your clip length, and storage needed.
- `token_counter_calculator`: Token Counter & Context-Window Fit Calculator — Estimate the token count of any text with the chars/4 words/0.75 heuristic, check if it fits 8k, 128k, 200k, or 1M context windows, and gauge API cost.
- `topsoil_calculator`: Topsoil Calculator (Yards & Weight) — Work out how much topsoil you need for a bed, lawn, or garden. Enter area and depth to get cubic yards, cubic feet, weight in tons, and the exact bag count.
- `turkey_cooking_time_calculator`: Turkey Cooking Time & Thaw Calculator — Estimate turkey roasting time by weight, plus refrigerator and cold-water thaw times. Stuffed or unstuffed, always cook to 165°F verified with a thermometer.