Developer Tools

10 tools

A focused collection of everyday developer utilities that run entirely in your browser. Format, encode, decode and validate data quickly without installing anything or sending your data to a server.

JSON Formatter

Format, beautify, minify and validate JSON instantly in your browser. Free, private, no upload required.

JSON Validator

Validate JSON instantly in your browser with precise line and column error reporting. Supports JSON Lines batch checking. Free, private, no upload.

Base64 Converter

Convert text to Base64 and back in your browser. Full UTF-8 support for Chinese, Japanese and emoji, with clear errors for bad padding.

URL Encoder / Decoder

Percent-encode and decode URL components in your browser with encodeURIComponent. Detects malformed % sequences and handles Unicode safely.

JWT Decoder

Decode any JSON Web Token in your browser. Pretty-prints header and payload, shows the signature, and checks whether the token is expired.

UUID Generator

Generate cryptographically random UUID v4 strings in your browser. Batch up to 1000, choose uppercase or compact form, copy or download as a file.

Timestamp Converter

Convert Unix timestamps to local and UTC dates and back. Auto-detects seconds vs milliseconds, shows the current time, and copies values in one click.

Regex Tester

Test regular expressions live in your browser. Highlight every match, list capture groups, and get a clear error when the pattern is invalid.

SQL Formatter

Format and beautify SQL in your browser. Choose PostgreSQL, MySQL, SQLite, BigQuery, T-SQL and more, pick indentation, then copy or download.

Markdown Editor

Write Markdown on the left and see a live sanitized preview on the right. Copy or download the rendered HTML. Runs entirely in your browser.