All tools
20 free tools that run entirely in your browser. Search or filter by category.
Percentage Calculator
Free percentage calculator: find what percent of a number, what a value is as a percentage, and percentage increase or decrease. Works instantly in your browser.
CalculatorsAge Calculator
Calculate your exact age in years, months and days from a date of birth, plus total weeks and days and your next birthday. Private and instant.
CalculatorsDate Difference Calculator
Find the number of days, weeks, months and years between two dates. Includes a calendar-accurate breakdown and works entirely in your browser.
CalculatorsRandom Number Generator
Generate one or many random integers in any range using your browser's cryptographically secure randomness. Optional unique values and no modulo bias.
GeneratorsPassword Generator
Create strong, random passwords with adjustable length and character sets. Uses cryptographically secure randomness and shows estimated strength. Nothing is sent anywhere.
GeneratorsWord & Character Counter
Count words, characters (with and without spaces), sentences, paragraphs and lines, plus an estimated reading time. Live, private and accurate for any text.
Text toolsText Case Converter
Convert text between UPPERCASE, lowercase, Title Case, Sentence case, camelCase, PascalCase, snake_case, kebab-case and more. Instant and private.
Text toolsRemove Duplicate Lines
Remove duplicate lines from any list or text, with options to ignore case, trim whitespace, drop empty lines and sort the result. Fast and private.
Text toolsUnit Converter
Convert between metric and imperial units for length, weight, volume, area, speed and digital storage. Accurate factors, instant results, no tracking.
ConvertersTemperature Converter
Convert temperatures between Celsius, Fahrenheit and Kelvin instantly. Includes absolute-zero validation. Private, browser-based and free.
ConvertersBMI Calculator
Calculate Body Mass Index from height and weight in metric or imperial units, with the standard BMI category. Includes a neutral, informational disclaimer.
CalculatorsLoan Payment Calculator
Estimate the monthly payment, total interest and total cost of a fixed-rate loan from the amount, interest rate and term. Private and instant.
CalculatorsTime Zone Converter
Convert a date and time from one time zone to another and compare multiple cities side by side. Uses your browser's time-zone data — no API needed.
ConvertersUnix Timestamp Converter
Convert Unix epoch timestamps (seconds or milliseconds) to human-readable UTC and local dates, and convert dates back to timestamps. Instant and private.
ConvertersQR Code Generator
Generate QR codes for URLs, text, Wi-Fi and more directly in your browser. Adjust size and error correction, then download a PNG. No tracking, no uploads.
GeneratorsURL Encoder / Decoder
Encode text for safe use in URLs or decode percent-encoded URLs back to readable text. Unicode-safe, instant and entirely browser-based.
ConvertersJSON Formatter & Validator
Format (pretty-print), minify and validate JSON in your browser. Clear error messages with line numbers. Your data is never uploaded.
DeveloperBase64 Encoder / Decoder
Encode text to Base64 or decode Base64 back to text, with UTF-8 support and an optional URL-safe variant. Instant, private and browser-based.
ConvertersColor Converter
Convert colors between HEX, RGB and HSL with a live preview and a color picker. Copy any format instantly. Browser-based and private.
ConvertersCountdown Calculator
Count down to any date and time and see the days, hours, minutes and seconds remaining, updating live. Also counts business days. Private and free.
Calculators