10 Free Tools

Free Developer Tools Online

Format JSON, encode Base64, convert CSV to JSON, generate colors, and more — all free developer utilities that run in your browser with no sign-up required.

No Sign-upClient-Side ProcessingWorks on Mobile100% Free

JSON Tools

JSON FormatterFormat, validate, and pretty-print JSON.

Convert & Transform

CSV to JSONConvert CSV spreadsheet data to JSON format.

Encode & Decode

Base64 Encoder / DecoderEncode text or files to Base64 and decode Base64 strings.URL Encoder / DecoderPercent-encode URLs or decode encoded URL strings.

Test & Debug

Regex TesterTest regular expressions with real-time match highlighting.Timestamp ConverterConvert Unix epoch timestamps to human-readable dates.

Design & Color

Color PickerPick colors from images and get HEX, RGB, HSL values.Gradient GeneratorBuild custom CSS linear and radial gradients.Tailwind ColorsBrowse and copy all Tailwind CSS color palettes.Favicon GeneratorGenerate favicons in all required sizes from any image.

What Are These Developer Tools?

These free developer utilities solve everyday tasks that programmers, DevOps engineers, and web developers encounter repeatedly — formatting a JSON response to read it clearly, converting a CSV export to JSON for an API, encoding a binary file to Base64, or picking the exact hex color for a design system.

All tools run entirely in the browser. No data is sent to a server — which matters when you are working with API responses, config files, or environment data that should stay private.

Frequently Asked Questions

Are these developer tools free?+

Yes. Every developer tool on this page is completely free to use with no account required.

Do these tools work offline?+

Most tools run entirely in your browser using JavaScript. Once the page is loaded, many tools work without an active internet connection.

Is my data sent to a server?+

No. All processing happens client-side in your browser. Your code, JSON, or text never leaves your device.

Can I use these tools on mobile?+

Yes. All developer tools are mobile-responsive and work on phones and tablets.

Explore Other Tool Categories

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