Free Tools

A handpicked toolkit of free online tools.

Sixteen sites we trust for the small jobs that come up every day — calculators, converters, decoders, and developer utilities. All free, all browser-only, all worth bookmarking.

Everyday calculators

For the math you don't want to do twice.

⬜
Square Footage Calculator
Calculate the area of rooms, lots, and surfaces in square feet, square meters, and more.
%
Percentage Calculator
Every percentage variant — of a number, increase, decrease, difference, and more.
⌛
Age Calculator
Calculate exact age in years, months, days, hours, minutes — between any two dates.
↔
Unit Cheatsheet
Engineering and scientific unit reference — converters, cheat sheets, and printable charts.
🕐
Clock With Us
Online clock with world time, time zones, and timing utilities in one place.
Text & writing utilities

For words, not numbers.

📝
Word Counter
Count words, characters, sentences, and paragraphs as you type. Reading time too.
↻
Text Repeat
Repeat any text N times with optional separators. For testing, padding, or formatting.
🔐
Password Strength Checker
Test how strong a password is and how long it would take to crack. Browser-only.
Developer utilities

For when you just need it now.

{ }
Base64 Encode / Decode
Convert text and files to and from Base64. Supports UTF-8, files, and data URLs.
%2F
URL Encode / Decode
Percent-encode or decode URLs and query parameters. Component vs full URI modes.
{ }
JSON Tools
Format, validate, minify, and convert JSON. Diff two JSON files side by side.
#
Hash Generator
Generate MD5, SHA-1, SHA-256, SHA-512 hashes from text or files. All client-side.
ID
UUID Generator
Generate UUID v1, v4, v7 and other versions. Bulk generation supported.
⏱
Epoch / Unix Time
Convert between Unix timestamps and human-readable dates across time zones.
⌗
Crontab Helper
Build and decode crontab expressions with plain-English explanations.
/^$/
Regex Guide
Build and test regular expressions with a reference library and live explanations.