Free Online Tools
Fast, free calculators, converters and generators. No sign-up — everything runs in your browser.
Calculators
Percentage Calculator
Find any percentage: X% of Y, what percent X is of Y, and percent change.
BMI Calculator
Check your body mass index in metric or imperial units with WHO category labels.
Age Calculator
Find your exact age in years, months, and days plus total days lived and days until your next birthday.
Tip Calculator
Calculate tip amount, total bill, and per-person share with preset and custom tip rates.
Loan Calculator
Estimate monthly payments, total interest, and total cost of an amortizing loan.
Compound Interest Calculator
See how principal grows with compounding interest by year, quarter, month, or day.
GPA Calculator
Compute weighted GPA on a 4.0 scale from course letter grades and credits.
Date Calculator
Find the difference between two dates or add and subtract days from any date.
Converters
Length Converter
Convert millimeters, centimeters, meters, kilometers, inches, feet, yards and miles instantly.
Weight Converter
Convert grams, kilograms, tonnes, ounces, pounds and stones with precise factors.
Temperature Converter
Convert Celsius, Fahrenheit and Kelvin using the exact thermodynamic formulas.
Data Storage Converter
Convert bytes, KB, MB, GB, TB and KiB, MiB, GiB, TiB with the correct SI or IEC factor.
Speed Converter
Convert meters per second, kilometers per hour, miles per hour and knots instantly.
Time Converter
Convert seconds, minutes, hours, days, weeks and years with standard time constants.
Color Converter
Convert HEX to RGB and HSL with a live color preview swatch.
Base64 Encoder / Decoder
Encode and decode Base64 text safely, including Unicode characters.
URL Encoder / Decoder
Encode and decode URLs and URL components safely for the web.
Generators
Password Generator
Generate strong random passwords locally — nothing leaves your browser.
UUID Generator
Generate random UUID v4 identifiers locally in your browser.
Lorem Ipsum Generator
Create classic placeholder text for mockups and wireframes.
QR Code Generator
Turn text or URLs into downloadable QR codes privately.
Random Number Generator
Generate unbiased random integers with your browser's crypto API.