Free calculators
34 calculators with formulas, worked examples and shareable results. Everything runs privately in your browser.
💰 Money & Loans
Loans, mortgages, interest, savings and debt — the decisions that cost or earn you the most.
Loan EMI Calculator
Monthly payment, total interest and yearly breakdown for any fixed-rate loan.
Mortgage Calculator
Full monthly housing cost: principal & interest, property tax, insurance and HOA.
Compound Interest Calculator
Grow a lump sum plus monthly contributions with any compounding frequency.
Simple Interest Calculator
Interest on principal only — for short loans, bonds and promissory notes.
Savings Goal Calculator
How much to save each month to hit a target by a deadline.
Monthly Investment (SIP) Calculator
Systematic monthly investing with an optional yearly step-up.
Retirement Calculator
Project your nest egg and the yearly income it can support.
Inflation Calculator
Future cost of today's money and how much purchasing power erodes.
Credit Card Payoff Calculator
Months to debt-free and total interest at your monthly payment.
Debt-to-Income (DTI) Calculator
The ratio lenders use to judge whether you can take on more debt.
📈 Business & Pricing
Margins, break-even, ROI, unit economics and runway for founders and small businesses.
Profit Margin Calculator
Gross profit, margin and markup from cost and selling price.
Markup Calculator
Selling price from cost and markup — with the margin it really gives.
Break-Even Calculator
Units and revenue needed to cover fixed costs.
ROI Calculator
Total and annualized return on any investment or campaign.
CAC & LTV Calculator
Customer acquisition cost, lifetime value, LTV:CAC and payback period.
Startup Runway Calculator
How many months your cash lasts, with revenue growth.
Price From Target Margin
The price you must charge to hit a target gross margin.
Freelance Hourly Rate Calculator
The hourly rate that actually pays your target income after costs and tax.
🤖 Websites, Creators & AI
Ad revenue, site valuation, domain flips, AI costs and creator earnings.
Ad Revenue (RPM) Calculator
Estimate display-ad earnings from pageviews and page RPM, with growth.
Website Valuation Calculator
Estimate a content site's sale value from profit and an earnings multiple.
Domain Flip Profit Calculator
Net profit and annualized return on buying, holding and selling a domain.
AI API Token Cost Calculator
Monthly cost of an AI feature from requests, tokens and per-million pricing.
AI Automation ROI Calculator
Value of hours saved by AI tools versus their monthly cost.
YouTube Earnings Calculator
Estimate creator ad income from monthly views and RPM.
Affiliate Earnings Calculator
Commission income from traffic, click-through and conversion rates.
Lead Value & Cost Calculator
What each lead is worth — and the most you can afford to pay for one.
Conversion Rate Calculator
Conversion rate and the traffic you need to hit a goal.
🔢 Everyday Numbers
Percentages, discounts, tips, taxes and price comparisons — fast answers.
Discount Calculator
Sale price with stacked discounts and what you really save.
Sales Tax / GST / VAT Calculator
Add tax to a net price or extract tax from a tax-inclusive price.
Hourly ↔ Salary Converter
Convert an hourly wage to weekly, monthly and annual pay.
Percentage Calculator
X% of Y, what percent A is of B, and the reverse.
Percentage Change Calculator
Increase or decrease between two values, as a percent.
Tip & Bill Split Calculator
Tip amount and each person's share.
Unit Price Comparison
Which pack size is really cheaper per unit.