Free calculators
Online CalculatorRun basic arithmetic with keyboard support, decimals, percent, clear, and backspace.
Percentage CalculatorSolve percent-of, percent-share, and percentage change questions.
Tip CalculatorCalculate tip, total, and per-person split amounts.
Unit ConverterConvert length, weight, temperature, and volume values live in your browser.
Age CalculatorCalculate age from a birth date to today or a custom reference date.
Date CalculatorAdd or subtract days, weeks, months, or years from a date.
Week Number CalculatorFind the ISO week number, ISO year, weekday, and week range for a date.
Choose the calculation you need
Each calculator focuses on one practical task and keeps the calculation in the browser. The group page connects related calculators under one subdomain.
Common calculation workflows
- Run arithmetic, percentage, and tip calculations quickly.
- Convert units for length, weight, temperature, and volume.
- Calculate age, dates, and ISO week numbers.
- Use static calculators without accounts or server-side storage.
Frequently asked questions
Are these calculators free?
Yes. The calculators are static browser tools designed to be free to use.
Do calculations run on a server?
No. The calculations run locally in the browser.
Why are date tools part of Calculators?
They answer calculation-oriented questions and fit the same search and user workflow cluster.
How should new calculators be integrated?
Add the calculator to this group page and link it from existing calculator apps through the related-tools line.