Fibonacci ToolBox

JWT decoder

Decode a JSON Web Token's header and claims and explain its lifetime. The signature is not verified.

JWT decoder options
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Base64

Encode text or files to Base64 (or a data: URI), and decode Base64 back to text or a file.

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URL encode / parse

Percent-encode and decode text, or break a URL into its parts and query parameters.

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HTML entities

Escape text for safe use in HTML, or turn entities back into characters.

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Number base converter

Convert integers between binary, octal, decimal, hex and base36 of any size.

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