Free tools.
A curated set of free, no-signup, single-purpose tools we recommend — calculators, encoders, generators, and references for engineers, developers, and writers. All open in a new tab.
Square Footage Calculator
Compute square footage of rooms, lots, or odd shapes — including triangles, circles, and multi-segment layouts.
Percentage Calculator
Every variant of the percentage question: X% of Y, X is what % of Y, percent change, tip splitting.
Age Calculator
Exact age in years, months, days, hours — plus age difference between two dates.
Base64 Encode / Decode
Quick Base64 conversion for strings and files. Useful for embedding images in CSS or decoding JWT tokens.
URL Encode / Decode
Percent-encoding for URLs, including form data. Handles all reserved characters per RFC 3986.
Password Strength Checker
Test password entropy and resistance to common attacks. Runs entirely in your browser; nothing transmitted.
Word Counter
Word, character, sentence, and paragraph counts with reading-time estimate. For essays, articles, and posts.
UUID Generator
Generate UUIDs (v1, v4, v5, v7) in bulk. With validation and format conversion.
JSON Tools
Format, validate, minify, and diff JSON. Plus JSON-to-CSV and schema inference.
Hash Generator
Compute MD5, SHA-1, SHA-256, SHA-512 for strings or files. All hashing runs client-side.
Epoch Time Converter
Convert between Unix timestamps and human-readable dates in any timezone.
Text Repeater
Repeat any text N times with optional separators. Useful for test data, padding, and stress-testing inputs.
Crontab Cheat Sheet
Decode and build cron expressions with a visual editor. Common schedules with one click.
Regex Guide
An interactive reference for regular expressions with examples and a tester for all common flavors.
Hours Calculator
Free hours and timesheet calculator with overtime and pay. Handles breaks, overnight shifts, and decimal hours.
Clock With Us
Online alarm clock, timer, stopwatch, world clock, and time zone converter — all browser-based, no signup.
These are external sites we like and use. We're not paid to list them, and we don't track outbound clicks. If you've made a free, useful single-purpose tool you'd like considered for this page, get in touch.