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406 free calculatorsfor money, health, math, and daily life.

Loans, mortgages, BMI, percentages, salary, tax, business, cooking, travel, and science. Every calculator shows the formula in plain language.

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406working calculators
22practical categories
85focused collections

All calculators

406 calculators.Pick one and start.

Search the name you already know, or pick a category. Every card opens a calculator with its formula and a plain explanation.

How to find a calculator

  1. 01SearchType mortgage, BMI, tip…
  2. 02FilterChoose 1 of 22 categories
  3. 03OpenStart with a clear result

Finance

51

Loans, mortgages, investing, savings, retirement, debt, and taxes.

LoansLoan

Estimate monthly payments, total interest, and the full cost of a fixed-rate loan.

LoansPersonal Loan

See the payment when an origination fee is financed into the amount borrowed.

LoansBusiness Loan

Estimate payments for a loan that starts with an interest-only period.

LoansStudent Loan

Estimate the payment after in-school interest is capitalized.

Business

32

Profitability, pricing, sales, marketing, and workforce estimates.

ProfitabilityProfit Margin

Divide profit by revenue for a period.

ProfitabilityGross Margin

Divide revenue minus the cost of goods by revenue.

ProfitabilityNet Profit Margin

Remove goods, operating costs, interest, and tax, then divide by revenue.

ProfitabilityMarkup

Divide the amount added to cost by the cost.

Salary & Work

8

Pay conversions, a paycheck, and a work schedule.

PaySalary

Convert hourly, weekly, monthly, and yearly gross pay.

PayHourly to Salary

Multiply an hourly rate by the weeks you work.

PaySalary to Hourly

Spread an annual salary across the weeks you work.

PayPaycheck

Divide annual gross pay into one paycheck.

E-commerce

14

Fees, shipping, packaging, and inventory for a shop.

PricingProfit

See profit after product cost, a percent fee, and shipping.

MarketplaceMarketplace Fee

Take a percent fee off one item price.

MarketplaceSeller Fee

Add a referral percent and a flat fee.

MarketplaceMarketplace Profit

Subtract cost, a referral, and a flat fee from the price.

Everyday

7

Bills, unit prices, age, and clock time.

MoneyTip

Add a percentage tip and split the bill.

MoneySplit Bill

Share a bill when one person owes an extra amount.

MoneyUnit Price

Divide a price by the quantity.

MoneyPrice per Unit

Compare the unit price of two offers.

Math

40

Percentages, arithmetic, fractions, algebra, geometry, and statistics.

PercentagesPercentage

Find a percent of a number, a ratio, or a percent change.

PercentagesPercentage Increase

Add a percent to a starting value.

PercentagesPercentage Decrease

Remove a percent from a starting value.

PercentagesPercentage Change

Measure the signed change from a starting value to a new value.

Every calculator

Need a different calculator?

Every category stays searchable, from loans and health to cooking, travel, and science.

Browse all 406 calculators

A clearer workflow

From your question to a result you can use.

Every calculator follows the same simple path, so you can move from a real-life question to a transparent answer without learning a new interface each time.

  1. 01 / Choose

    Find the right calculator.

    Search by the words you already use or browse a focused category.

  2. 02 / Calculate

    Enter the numbers you know.

    Clear labels, useful examples, and immediate validation keep the inputs understandable.

  3. 03 / Understand

    Check what the result means.

    See the formula, assumptions, definitions, worked example, and limitations behind the answer.

Built for confidence

Know what the answer means.

A trustworthy calculator makes the method visible and explains where the result should—and should not—guide a decision.

01
Start with only the values that matter.

Clear labels, units, and sensible defaults help you enter the right information.

01

Transparent methods

Published calculators show their formula and assumptions.

02

Plain-language guidance

Definitions and examples help you use each input correctly.

03

Private by default

Core calculations run in your browser without an account.

04

Accessible anywhere

Readable controls work across phone, tablet, and desktop.

Good to know

Questions before you begin.

Short answers about choosing a calculator, formulas, and privacy.

01Are these calculators free to use?

Yes. Every published calculator is free to use and shows a result without an account or subscription.

02How do I know which calculator to choose?

Search for the calculator by name, or pick a category. Related calculators stay grouped, and each one explains when it is the right tool.

03Where do the formulas come from?

Each live calculator documents its formula, assumptions, input definitions, worked example, and important limitations beside the tool.

04Do you store the numbers I enter?

Core calculations run in your browser. The library does not require an account, and raw financial or health inputs are not needed for analytics.

Ready to calculate?

Start with the question you have today.

Explore all 406 calculators