DevKit
Open source — star us on GitHub

Every developer tool you need. One beautiful place.

17 fast, free tools that run entirely in your browser. No sign-ups, no uploads, no limits.

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JSON Formatter

Format, validate and minify JSON with configurable indentation.

Formatters

JWT Decoder

Decode JWT tokens and inspect header, payload and expiry claims safely in your browser.

Security

Regex Tester

Test regular expressions live with match highlighting, capture groups and flags.

Testers

Base64 Encoder / Decoder

Encode and decode Base64 text with full Unicode support.

Converters

SQL Formatter

Pretty-print SQL for PostgreSQL, MySQL, SQLite, T-SQL and more.

Formatters

Timestamp Converter

Convert Unix timestamps to human dates and back, with a live epoch clock.

Converters

UUID Generator

Generate cryptographically secure UUID v4 identifiers in bulk.

Generators

Markdown Previewer

Write Markdown and see a sanitized live preview side by side.

Formatters

Diff Checker

Compare two texts line by line and highlight additions and deletions.

Utilities

Cron Parser

Explain cron expressions in plain English and preview the next scheduled runs.

Utilities

Hash Generator

Compute SHA-1, SHA-256, SHA-384 and SHA-512 hashes instantly.

Security

Color Converter

Convert colors between HEX, RGB and HSL with instant shade palette.

Converters

URL Encoder / Decoder

Encode and decode URLs and URI components, with percent-encoding control.

Converters

HTML Entities

Escape and unescape HTML entities, including numeric character references.

Converters

Number Base Converter

Convert numbers between binary, octal, decimal and hexadecimal.

Converters

Lorem Ipsum Generator

Generate placeholder paragraphs, sentences or words for mockups.

Generators

Image Compressor

Compress and resize images locally in your browser — nothing is uploaded.

Utilities

Privacy first

Every tool runs 100% client-side. Your tokens, data and images never touch a server.

Blazingly fast

Statically generated pages with zero backend. Tools open instantly and work offline.

Built by everyone

Adding a tool is one component plus one registry entry. First PR friendly by design.

Have an idea for a tool?

DevKit grows through community contributions. Ship your favorite utility in under an hour — no framework expertise required.