# <eat-sleep-code /> Calculator

> Free online calculators for everyday math — fast, private, and fully client-side. No tracking, no server-side processing.

## Calculators

- [Percentage Calculator](https://calculator.eat-sleep-code.com/percentage-calculator): Calculate percent of a number, percentage change (increase/decrease), what percent one value is of another, and X out of Y total — with formula explanations.
- [Unit Converter](https://calculator.eat-sleep-code.com/unit-converter): Convert between units of distance, weight/mass, volume, temperature, speed, and cooking measurements. Includes a quick-reference conversion table.
- [Currency Converter](https://calculator.eat-sleep-code.com/currency-converter): Convert between 50+ world currencies using live exchange rates (via open.er-api.com). Remembers your last selected currencies.
- [Time Calculator](https://calculator.eat-sleep-code.com/time-calculator): Calculate date offsets (e.g. 90 days from today), the number of days between two dates, and convert times across world timezones with a live world clock.
- [Fuel Economy Calculator](https://calculator.eat-sleep-code.com/fuel-economy): Convert between MPG (US), MPG (UK), km/L, and L/100km. Includes trip cost estimator, EPA efficiency ratings, and an EV range standards converter (EPA / WLTP / NEDC / CLTC).
- [Mortgage Calculator](https://calculator.eat-sleep-code.com/mortgage-calculator): Calculate monthly mortgage payments including principal & interest, property tax, homeowner's insurance, PMI, and HOA. View full amortization schedule and see savings from extra payments. Supports 10, 15, 20, 30, and 40-year terms.
- [Loan Calculator](https://calculator.eat-sleep-code.com/loan-calculator): Standard mode calculates monthly payment from loan amount. Reverse mode calculates maximum loan from an affordable monthly payment. Includes rate comparison table and amortization schedule.

## About

Built by [eat-sleep-code](https://eat-sleep-code.com). Part of the eat-sleep-code suite of free web tools alongside [Toolbox](https://toolbox.eat-sleep-code.com), [Easel](https://easel.eat-sleep-code.com), and [Animator](https://animator.eat-sleep-code.com).