Free Online Developer Tools
Essential free utilities built for developers. Format and validate JSON, encode/decode Base64 and URLs, inspect JWT tokens, test regular expressions, minify HTML, CSS, and JavaScript, convert between data formats, and more — all running locally in your browser with zero setup and no data uploads.
JSON Formatter
Format, beautify, and validate JSON data online for free. Instantly prettify minified JSON with syntax highlighting and error detection. No signup required.
Base64 Encoder / Decoder
Encode text and files to Base64 or decode Base64 strings online for free. Essential tool for APIs, data URIs, and embedded content. No signup required.
URL Encoder / Decoder
Encode and decode URLs and query parameters online for free. Handle special characters, Unicode, and percent-encoding instantly. No signup required.
UUID Generator
Generate random UUID v4 identifiers online for free. Create single or bulk UUIDs for databases, APIs, and application development. No signup required.
JWT Decoder
Decode and inspect JWT tokens online for free. View header, payload, and signature claims with expiration validation. No signup required.
Regex Tester
Test and debug regular expressions online for free with real-time matching and group extraction. Supports JavaScript regex syntax. No signup required.
HTML Minifier
Minify HTML code online for free. Remove whitespace, comments, and unnecessary attributes to reduce file size and improve page load speed. No signup required.
CSS Minifier
Minify CSS stylesheets online for free. Remove whitespace, comments, and redundant rules to optimize your CSS for production. No signup required.
JavaScript Minifier
Minify JavaScript code online for free. Remove whitespace, comments, and shorten variable names to optimize your scripts for production. No signup required.
JSON ↔ CSV Converter
Convert between JSON and CSV formats online for free. Custom delimiters, auto-detection, and nested objects. No signup required.
XML ↔ JSON Converter
Convert between XML and JSON formats online for free. Parse XML to JSON or generate XML from JSON data. No signup required.
YAML ↔ JSON Converter
Convert between YAML and JSON formats online for free. Parse YAML configs to JSON or generate YAML from JSON. No signup required.
CSV Viewer
View, search, and analyze CSV files online for free. Get a sortable, filterable table with statistics. No signup required.
Base64 Image Encode / Decode
Encode images to Base64 or decode Base64 to images online for free. Generate data URIs for HTML and CSS. No signup required.
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Discover the best free browser-based developer tools of 2026. From JSON formatters and Base64 encoders to JWT decoders and regex testers — all with no signup required.
Read article →How to Format and Validate JSON Online in Seconds
Learn how to use a free JSON formatter to beautify, validate, and debug JSON data instantly in your browser. Includes tips for developers and API testing.
Read article →What Is Base64 Encoding? How to Encode and Decode Online
A plain-English explanation of Base64 encoding and when to use it. Learn how to encode text, files, and images to Base64 for free in your browser.
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