Online Developer Tools
Quick answer
Format JSON, decode JWTs, convert colors, generate passwords, and test regular expressions — all in your browser, without installing extensions or external tools.
JSON Formatter
Format, validate and minify JSON.
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Base64 Encoder/Decoder
Encode and decode Base64.
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Password Generator
Generate strong, random passwords in your browser.
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Color Converter
Convert colors between HEX, RGB, HSL and HSV.
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QR Code Generator
Create QR codes and download them as PNG or SVG.
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UUID Generator
Generate UUID v4 in bulk, in your browser.
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Case Converter
UPPER, lower, Title, camelCase, snake_case and more.
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JWT Decoder
Read the header and payload of a JWT token.
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Text Comparator
Compare two texts and highlight differences line by line or word by word.
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Regex Tester
Test regular expressions in real time and highlight matches in your text.
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What you can do with the dev tools
- Format and validate JSON from API responses, config files, and error logs
- Decode JWT tokens to inspect the header, payload, and expiration dates
- Convert colors between HEX, RGB, HSL, and HSV for use in CSS and design systems
- Generate strong passwords, UUIDs, and QR codes in bulk with a single click, entirely in the browser
Frequently asked questions
Are the developer tools free?
Yes. All tools in this category — JSON formatter, base64, password generator, color converter, QR code, UUID, case converter, JWT decoder, text diff, and regex tester — are completely free with no limits. No account needed.
Can I use the JSON formatter with large files?
Yes. The JSON formatter runs entirely in your browser and handles large files. The practical limit is the memory available on your device.
Does the JWT decoder verify the token signature?
No. The JWT decoder reads and formats the header and payload for inspection — it does not verify the cryptographic signature. Use a backend library to verify signatures.
Is my code or my passwords stored?
No. All developer tools run locally in your browser — nothing is sent to servers. Your passwords, tokens, and code stay on your computer.
Does the regex tester support JavaScript flags?
Yes. It supports the g, i, m, s, u, and y flags from the ECMAScript specification, and highlights matches in real time in your test text.