Free online developer tools

Format and validate JSON, SQL and HTML, minify CSS and JavaScript, encode Base64 and URLs, test regular expressions and generate UUIDs, meta tags, robots.txt files, sitemaps and slugs.

JSON Formatter

Format, validate and minify JSON, with clear error messages.
JSON to CSV Converter

Turn a JSON array into a CSV file you can open in Excel.
SQL Formatter

Beautify SQL queries for MySQL, PostgreSQL, SQL Server and more.
HTML Formatter

Beautify messy or minified HTML with clean indentation.
CSS Minifier

Make CSS files smaller so pages load faster.
JavaScript Minifier

Minify and compress JavaScript with Terser.
Base64 Encoder & Decoder

Encode text or files to Base64 and decode Base64 back to text.
URL Encoder & Decoder

Encode text for URLs and decode percent-encoded links.
Regex Tester

Test regular expressions with live highlighting and groups.
UUID Generator

Generate random version 4 or time-ordered version 7 UUIDs.
Meta Tag Generator

Create SEO title, description and social sharing tags.
Robots.txt Generator

Create a robots.txt file to guide search engine crawlers.
Sitemap Generator

Turn a list of page addresses into an XML sitemap.
Slug Generator

Convert titles into clean, URL-friendly slugs.

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Your code stays private

These tools run in your web browser. Your JSON, SQL, code and text are never sent to our server, so they are safe to use with private data.