JWT Decoder
This does not verify the signature
A JWT's header and payload are just Base64url-encoded JSON — anyone can read them without a key, which is what this tool does. Checking the third part, the signature, requires the secret (for HS*) or public key (for RS*/ES*) that signed the token, which this browser-only tool never has and never asks for. The signature above is shown exactly as it appears in the token, undecoded — treat any claims you see as unverified until you check them against the real signing key server-side.
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Text
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- Diff CheckerLine-by-line diff of two text blocks via LCS.
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- Unicode Code Point InspectorPer-character code point, U+ hex value and UTF-8 byte length, including emoji outside the BMP.
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Code & data
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- Base64 Encoder / DecoderEncode or decode Base64 with Unicode support.
- XML FormatterPretty-print and validate XML, with clear errors on mismatched tags.
- JSON Path EvaluatorPull a value out of JSON with a simple dot/bracket path.
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- HTML FormatterIndent nested HTML tags, with void elements handled correctly.
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- JSON Diff CheckerStructural differences between two JSON documents.
- INI / Properties File ParserConvert INI or .properties key=value files to JSON and back.
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- .env File ParserConvert a .env file to JSON and back, comments and quotes intact.
- CSV Diff CheckerRow-by-row and cell-by-cell differences between two CSV files.
Encoding
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- HTML Entity Encoder / DecoderEscape or unescape HTML entities like & and <.
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- String Escape / UnescapeEscape or unescape strings for JSON/JS literals or regex patterns.
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Web & Network
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Numbers & CS
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- Big-O Complexity ReferenceBrowsable reference of common time-complexity classes.
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Color & Design
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Date & Time
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Generators
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- License Text GeneratorFull open-source license text — MIT, Apache-2.0, GPL-3.0 and more.