Free online calculators and converters
No install, no sign-up. Everything runs in your browser and nothing is uploaded.
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Developer tools — all
JSON, Base64, JWT, and hashing utilities that run entirely client-side.
JSON Formatter & ValidatorFormat, minify, and validate JSON with precise error locations.Developer toolsBase64 Encoder & DecoderEncode and decode Base64 text and files, including URL-safe variants.Developer toolsJWT DecoderDecode JWT headers and payloads and read expiry claims in human-readable form.Developer toolsHash GeneratorCompute SHA-256, SHA-1, SHA-512, and MD5 hashes for text or files.Developer tools