Calculator Website
Free calculators that show their work. Enter your numbers, get an answer instantly, and check the math — no sign-up, no download. New calculators added every week — come back and see what's new.
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💰 Money
Payments, payoff, pay, and savings — mortgage, loans, compound interest, budgets and more.
25 tools🏠 Home & Construction
Concrete, paint, flooring, solar and project costs.
10 tools❤️ Health
BMI, calories, macros, sleep and more.
12 tools📈 Wealth & Real Estate
Rentals, flips, dividends and retirement projections.
11 tools✈️ Travel
Trip budgets, fly-vs-drive, jet lag.
10 tools🏕️ Tiny Home
Lot fit, trailer weight, solar sizing.
8 tools🔌 Off-Grid
Battery banks, rainwater, generators.
5 tools🏦️ Banking
Savings APY, CDs, fee comparison.
4 toolsHome & Construction
Material and project calculators for building, fixing, and quoting jobs.
- Concrete Calculator — slabs, footings, and bag counts, with waste included.
- Mulch, Soil & Gravel Calculator — cubic yards and bag counts for beds and paths.
- Paint Calculator — gallons by room size, doors, windows, and coats.
- Fence Calculator — posts, pickets, and rails for any fence run.
- Square Footage Calculator — area for rooms, floors, and lots.
- Contractor Quote Estimator — price a small job from real costs, with exclusions in writing.
- Solar Savings Calculator — simple payback estimate from your own bill, system cost, and bill offset.
- Flooring Calculator — boxes and square footage for a room, with waste included.
- Tile Calculator — tiles and boxes needed for a floor or wall, with waste.
- Electricity Cost Calculator — what an appliance costs to run per month, from your own kWh price.
Money
Payments, payoff, pay, and savings — estimates only, not financial advice.
- Mortgage Payment Calculator — monthly payment, total interest, and total cost.
- Mortgage Payoff Calculator — how extra payments shorten a loan and save interest.
- Loan Payment Calculator — monthly payment and total interest for any fixed-rate loan.
- Loan Payoff Calculator — months to pay off a loan at a fixed payment.
- Auto Loan Calculator — monthly car payment from price, down payment, and trade-in.
- Credit Card Payoff Calculator — months to pay off a card balance, and the interest it costs.
- Salary / Hourly Calculator — convert pay between hourly, weekly, monthly, and annual.
- Overtime Pay Calculator — regular pay, overtime pay, and total pay.
- Compound Interest Calculator — how savings grow with regular contributions.
- Retirement Savings Calculator — projected savings at retirement.
- Rent vs. Buy Calculator — simplified comparison over the years you plan to stay.
- Home Affordability Calculator — max home price from the 28/36 rule.
- Mortgage Refinance Calculator — monthly savings and break-even time.
- Debt Payoff Calculator — snowball vs. avalanche for up to 3 debts.
- Savings Goal Calculator — monthly saving needed to reach a goal.
- Emergency Fund Calculator — target fund from essential expenses.
- 50/30/20 Budget Calculator — needs, wants, and savings split.
- Net Worth Calculator — assets minus liabilities.
- Student Loan Calculator — payment, interest, and extra-payment savings.
- Sales Tax Calculator — tax and total from a price and your own local rate.
- Amortization Calculator — monthly payment, total interest, and payoff time with a yearly summary.
- Simple Paycheck Calculator — take-home pay from gross pay, a tax percentage you enter, and deductions.
- Debt-to-Income Ratio Calculator — monthly debt payments as a share of gross income.
- Salary Raise Calculator — new salary, yearly increase, and monthly increase from a raise percentage.
- Investment Fee Drag Calculator — ending value with and without a yearly fee, at a return you enter.
Health
General-information estimates only — see a professional for personal health decisions.
- BMI Calculator — body mass index and standard category.
- BMR Calculator — calories burned at rest, by Mifflin-St Jeor.
- Calorie / TDEE Calculator — daily calorie needs from BMR and activity.
- Body Fat Calculator — US Navy method estimate from measurements.
- Ideal Weight Calculator — healthy weight range and Devine ideal weight.
- Water Intake Calculator — daily water in litres and cups.
- Waist-to-Hip Ratio Calculator — ratio and WHO risk category.
- Heart Rate Zones Calculator — max heart rate and five training zones.
- Sleep Cycle Calculator — bedtimes and wake times on 90-minute cycles.
- Macro Calculator — protein, carb and fat grams from daily calories and a split.
- Protein Intake Calculator — daily protein range from weight and activity level.
- Ovulation Calculator — estimated ovulation, fertile window and next period — estimate only.
Everyday Tools
Quick math for daily life.
- Percentage Calculator — percent of, what percent, and percent change.
- Tip Splitter Calculator — tip, total, and per-person share.
- Age Calculator — exact age in years and days.
- Date Duration Calculator — days, weeks, and months between dates.
- Discount Calculator — sale price after discount and tax.
- GPA Calculator — weighted GPA on a 4.0 scale.
- Fuel Cost Calculator — gallons, total fuel cost, and cost per mile for a trip.
- Unit Converter — length, weight, temperature, area, and volume, US and metric.
- Scientific Calculator — powers, roots, trig in degrees, logs, and factorial.
- Final Grade Calculator — the final exam grade you need for your target grade.
- Recipe Scaler Calculator — scale ingredient amounts from one serving count to another.
- Dog Age Calculator — approximate human-age equivalent for your dog.
Dating & Relationships
Fun and practical date math — love scores are for fun only.
- Time Together Calculator — years, months, days together and next anniversary.
- Age Gap Calculator — age difference and each person's current age.
- Love Compatibility Calculator — name-based score, for fun only.
- Anniversary Countdown Calculator — days until the next anniversary.
- Due Date Calculator — estimated due date and trimester dates.
Gold & Crypto
Gold and crypto estimates at prices you enter — never live prices, and not financial advice.
- Crypto Profit Calculator — profit and loss from buy and sell prices you enter.
- Crypto DCA Calculator — value of a regular monthly crypto purchase.
- Crypto Converter Calculator — coins to dollars at a price you enter, and satoshis to bitcoin.
- Gold Value Calculator — melt value by weight, karat, and a price per troy ounce you enter.
- Gold Weight Converter — grams, ounces, troy ounces, kilograms, and pennyweights.
QR Code Generator
Free QR codes for links, Wi-Fi, email, text, and contacts — no sign-up, no watermark.
Fishing
Estimates for the water — length, line, drag, depth and sinkers.
- Fish Weight Estimator — length and girth to estimated pounds and kilograms.
- Reel Line Capacity Calculator — how many yards of a new line diameter fit your spool.
- Drag Setting Calculator — recommended drag range from line breaking strength.
- Trolling Depth Calculator — approximate lead-core depth by colours and speed.
- Sinker Weight Calculator — a starting-point sinker size from current and depth.
Sports
Running, lifting and training estimates.
- Running Pace Calculator — pace, time or distance, plus race splits.
- One Rep Max Calculator — Epley and Brzycki 1RM estimates with a training table.
- Calories Burned Calculator — energy by activity, weight and duration.
- VO2 Max Calculator — aerobic fitness estimate from a 12-minute Cooper test.
- Steps to Distance Calculator — steps to miles and kilometres, with estimated calories.
Architecture
Preliminary estimates only — not engineering advice, not a code approval. Confirm with a licensed engineer and your local building code before building.
- Stair Calculator — risers, treads, run and stringer length.
- Roof Pitch Calculator — pitch, angle, multiplier and rafter length.
- Board Feet Calculator — lumber volume from thickness, width, length and count.
- Wall Studs Calculator — studs and plates for a straight wall.
- Drywall Calculator — sheets for walls and ceiling, with waste.
- ADA Ramp Calculator — ramp run at a 1:12 slope, with landing guidance.
- Foundation Square-Up Calculator — diagonal and 3-4-5 check.
- Arch Radius Calculator — radius and arc length from span and rise.
Tiny Home
Preliminary estimates only — trailer, code, and local rules vary. Check your local rules before building, moving, or parking a tiny home.
- Tiny Home Lot Fit Calculator — does the home fit the lot after setbacks?
- Tiny Home Trailer Weight Calculator — GVWR remaining and per-axle load from your own weights.
- Tiny Home Loft Headroom Calculator — headroom at the centre and toward the eaves.
- Tiny Home Piers Calculator — piers per side and total from length and spacing.
- Tiny Home Cost Per Square Foot Calculator — total cost divided by square feet.
- Tiny Home Solar Panel Count Calculator — panels needed from daily watt-hours, panel wattage, and sun hours.
- Tiny Home Water Tank Days Calculator — days of water from tank size and daily use.
- Tiny Home Heating Load Calculator — rough BTU/hr guide from size and insulation.
Travel
Trip planning calculators. Rates, allowances, and limits are entered by you — never claimed from an airline, hotel, or exchange market.
- Trip Budget Calculator — total trip cost, per person, and per day.
- Road Trip Driving Cost Calculator — fuel, tolls, wear, and cost per mile.
- Fly vs Drive Calculator — total flying cost against total driving cost.
- Trip Cost Splitter Calculator — fair share and who owes whom.
- Time Zone Converter — home time to destination time from offsets you pick.
- Flight Time Calculator — airborne time and door-to-door time.
- Jet Lag Calculator — rough recovery-days guide only, not medical advice.
- Baggage Weight Calculator — bag weight against an allowance you enter; check your airline.
- Hotel Total Cost Calculator — room, tax, and fees to an all-in total.
- Currency Converter — conversion at a rate you enter; not a live rate.
Wealth & Real Estate
Rental, flip, and wealth-building estimates. All growth and return figures are assumptions you enter — estimates and projections, not predictions or financial advice.
- Rental Cash Flow Calculator — monthly and yearly cash flow from rent and costs.
- Cap Rate Calculator — net operating income, cap rate, and gross yield.
- House Flip Profit Calculator — profit and ROI from buy, rehab, holding, selling, and sale prices.
- Property Appreciation Calculator — future value projection at a growth rate you enter — not a prediction.
- Closing Costs Calculator — loan amount, closing costs, and total cash to close.
- Dividend Income Calculator — yearly and per-payout dividend income.
- Millionaire Timeline Calculator — years to $1,000,000 at a saving rate and return you enter.
- Home Equity Calculator — equity in dollars and percent from value and mortgage balance.
- Cash-on-Cash Return Calculator — yearly cash flow divided by cash invested.
- Retirement Withdrawal Calculator — yearly and monthly withdrawals at a rate you enter, with the 4% rule of thumb.
- Net Worth Projection Calculator — projected net worth from contributions and a growth rate you enter.
Off-Grid
Power, water, and backup estimates for off-grid and storm-ready living. All figures are estimates — confirm with a qualified professional before buying equipment.
- Battery Bank Sizing Calculator — battery capacity in amp-hours and kilowatt-hours from daily use, days of autonomy, voltage, and depth of discharge.
- Rainwater Collection Calculator — gallons collected from roof area, rainfall you enter, and collection efficiency.
- Generator Sizing Calculator — recommended size from running watts plus the largest starting surge, with a 20% margin.
- Generator Fuel Runtime Calculator — runtime hours and fuel per day from tank size and consumption you enter.
- Emergency Water Storage Calculator — total gallons and bottle equivalents for your household and outage length.
Towing
Towing and payload estimates only — confirm your door-sticker ratings, hitch class, tires, and brakes, and never exceed manufacturer ratings.
- Towing Capacity Calculator — max trailer by GCWR method, by payload method, and the limiting factor.
- Tongue Weight Calculator — tongue weight percentage and whether it is in range for conventional or fifth-wheel trailers.
- Payload Remaining Calculator — payload capacity, payload used, and payload remaining.
- Trailer Weight Calculator — loaded trailer weight and percentage of GVWR.
Homestead
Small-farm and backyard estimates. Prices and yields are figures you enter — results are estimates, not guarantees.
- Chicken Feed Cost Calculator — monthly feed cost and feed-only cost per dozen eggs.
- Seed Spacing Calculator — plants per row and rows needed for a target count.
- Raised Bed Soil Calculator — cubic feet, cubic yards, and bag counts for a raised bed.
- Sugar Syrup Calculator — sugar and water amounts by weight for 1:1 or 2:1 syrup.
- Honey Yield Calculator — total pounds and jars from hives and yield per hive.
Hunting
Ballistics and bow estimates only — rough estimates, not shooting solutions. Verify at the range and follow all firearm and bow safety rules.
- Arrow Kinetic Energy Calculator — kinetic energy and momentum from arrow weight and speed.
- Bullet Drop Calculator — a simplified, rough drop estimate only; it does not model drag, wind, altitude, temperature, or scope height properly.
- Draw Weight Calculator — estimated arrow speed from draw weight, draw length, and arrow weight by a stated rule of thumb, rough only.
Banking
Savings, CD, and fee estimates. All APYs and fees are figures you enter — no bank rate is claimed here, and results are estimates only, not financial advice.
- Savings APY Calculator — balance growth at an APY you enter, compounded monthly.
- CD Value Calculator — maturity value and interest from a deposit, an APY you enter, and a term.
- Bank Fee Comparison Calculator — yearly cost of two accounts from monthly fees you enter.
- CD Ladder Calculator — amount per rung and yearly maturing principal for a CD ladder.