Dev tools
Free tools for everyday development, plus a practice terminal to learn the command line safely.
Terminal New
A safe, simulated Linux shell with guided missions. Learn the command line without breaking anything.
JSON formatterPretty-print, minify and validate JSON with clear error positions.
Regex testerTest JavaScript regular expressions with live match highlighting and groups.
Diff viewerCompare two texts line by line and see what was added or removed.
Color pickerConvert between HEX, RGB and HSL and check text contrast.
Base64 encoderEncode and decode Base64, including Unicode text.
UUID generatorGenerate random version 4 UUIDs, one or many at a time.
Hash generatorMD5, SHA-1 and SHA-256 hashes of any text.
Timestamp converterConvert Unix timestamps to readable dates and back.
URL encoderPercent-encode and decode URLs and query strings.
Cron parserExplain a cron expression in plain words and list its next run times.
Password generatorStrong random passwords: choose the length and character sets.
JWT decoderRead the header, payload and dates of a JSON Web Token.
Case convertercamelCase, snake_case, kebab-case, Title Case and more.
Text statisticsWords, characters, sentences and reading time.
Lorem ipsumPlaceholder paragraphs for designs and mock-ups.
AI chat (demo)Try a chat assistant with scripted answers about coding topics.
Secret key generatorFlask, Django, Laravel, Rails and JWT secrets as ready-to-paste .env lines.
.gitignore generatorCombine ignore rules for your languages, frameworks, editors and OS.
chmod calculatorConvert Linux file permissions between checkboxes, octal and rwx.
HTTP status codesSearch every common HTTP status code and when to use it.
Number base converterDecimal, hex, binary, octal and base 36, for numbers of any size.
CSV ⇄ JSONConvert CSV to JSON and back, with quoted fields handled correctly.
SQL formatterFormat or minify SQL queries for reviews and documentation.
Subnet calculatorNetwork, broadcast, host range, mask and wildcard for any IPv4 CIDR.
Meta tags generatorSEO, Open Graph and X/Twitter tags for link previews, with length checks.
Stack recommenderAnswer a few questions, get a tech stack
SaaS cost calculatorEstimate hosting, database and payment costs
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