Format, minify, and validate JSON locally with useful errors.
Tool category
Developer
Format, encode, decode, validate, and inspect developer data locally.
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All developer
Format, minify, and validate JSON locally with useful errors.
Encode or decode Unicode text as Base64 locally.
Encode or decode URL components in your browser.
Create SHA-256, SHA-384, or SHA-512 hashes with Web Crypto.
Convert Unix timestamps and local dates in both directions.
Test JavaScript regular expressions with flags and match details locally.
Apply lightweight indentation to HTML, CSS, or JavaScript source locally.
Convert HEX, RGB, and HSL colors and preview the result.
Decode JWT headers and payloads locally without claiming signature validity.
Parse or build URL query strings locally.
Encode or decode HTML entities without sending content anywhere.
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About developer
Handle common development tasks such as formatting, encoding, decoding, validation, hashing, timestamps, URLs, and color conversion.
Choosing the right tool
Results are produced by browser APIs; always validate security-sensitive output in the context of the system where you will use it.
Built for focused, private work
Each card states whether work happens in your browser, on the Toolbox server for the current request, or through an external provider. No account is required.