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Fast, reliable, privacy-first. No signup required.
Format, beautify and validate JSON online for free.
Validate JSON syntax and find errors with line numbers.
Convert JSON data to CSV format online.
Convert CSV data to JSON format online.
Decode JWT tokens and inspect header, payload, and signature.
Generate JWT tokens with custom header and payload.
All processing happens in your browser. Your data never leaves your device.
Open and use any tool instantly. No accounts, no tracking, no friction.
Easy on the eyes, day or night. Automatic theme detection with manual override.
Fully responsive. Works great on phones, tablets, and desktops.
DevToolsHub is a collection of free, browser-based developer tools designed to simplify your daily workflow. Whether you are debugging an API response, decoding a JWT token, testing a regular expression, or formatting a SQL query, our tools help you get the job done quickly without installing anything or signing up.
In modern software development, developers frequently switch between small utility tasks — formatting JSON payloads, encoding strings to Base64, generating UUIDs, validating YAML configurations, and more. These tasks are repetitive but essential. Having a reliable set of online tools saves time and reduces context switching between different applications and environments.
Privacy by design. Every tool on DevToolsHub runs entirely client-side in your browser. Your data is never uploaded to a server, never logged, and never accessible to anyone but you. This means you can safely paste sensitive API keys, tokens, or configuration files into any tool without worrying about data leaks. There are no backend servers processing your input — all computation happens locally on your machine.
Common use cases. Developers use our JSON Formatter to pretty-print and validate API responses. The JWT Decoder helps inspect authentication tokens during debugging. The Regex Tester allows rapid iteration on regular expression patterns with live match highlighting. The Base64 Encoder/Decoder handles encoding for data URIs and API payloads. The SQL Formatter makes database queries readable. The UUID Generator creates unique identifiers for testing and database seeding. The Cron Generator builds schedule expressions for automated tasks. The Markdown Previewer renders documentation in real-time.
Built for speed. Our tools load instantly and process data in real-time. There are no server round-trips, no upload wait times, and no rate limits. You can work with large files and complex data without any performance bottlenecks. Everything is optimized for developer productivity.
Always free. DevToolsHub is and always will be free to use. No freemium tiers, no locked features, no premium plans. We believe essential developer tools should be accessible to everyone. The project is open source, and we welcome contributions from the community.
Explore our full collection of tools and discover how DevToolsHub can streamline your development workflow. Have a suggestion for a new tool? Let us know.
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