Free Developer Tools

A complete kit of privacy-first developer utilities — format and validate JSON, encode Base64, hash text, decode JWTs, test regular expressions, build cron schedules, design CSS gradients and preview Markdown. Everything runs entirely in your browser, so your code and secrets never touch a server.

Read the guide: A Practical Guide to Everyday Developer Encoding & Formatting Read the guide: Why In-Browser Tools Are More Private Than Uploading Files

Base64 Encode / Decode

Convert text or files to and from Base64 instantly in your browser.

Code Formatter

Beautify, minify and validate JSON, HTML, CSS, SQL, XML and YAML.

Regex Tester & Builder

Test patterns against text and build common regex from presets.

Slug / URL Encoder

Clean broken URLs or turn any title into a safe URL slug.

Hash Generator

Compute SHA-1/256/384/512 digests of any text, instantly on-device.

Color Converter

Convert HEX, RGB and HSL and check WCAG contrast in real time.

Unix Timestamp Converter

Convert between Unix time, ISO 8601 and human dates both ways.

JWT Decoder

Decode JWT header and payload locally — no secret, no upload.

Crontab Schedule Creator

Build and decode cron expressions with plain-English explanations and next run times.

Number Base Converter

Convert between binary, octal, decimal and hex — plus a bitwise calculator.

Text Encryptor

Password-protect text with AES-256 encryption, right in your browser.

Webmaster File Generator

Generate robots.txt, sitemap.xml and .htaccess files in seconds.

CSS Gradient Generator

Design linear, radial and conic CSS gradients with a live preview.

Markdown Previewer

Write Markdown and see the rendered HTML side by side, instantly.

Document Privacy Inspector

See what a PDF or Office file says about you, then strip it.

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