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    Developer · 9 Gizlets

    Developer tools

    These are for the text that passes between systems: payloads, tokens, encoded strings, exports, identifiers. Most of them read something you pasted and tell you what it is; a few turn it into something else.

    If what you have is unreadable and you are not sure what it is, the shape usually says. Three dot-separated chunks is a JWT, a string of letters ending in = is likely Base64, %20 and friends are percent-encoding, and a ten or thirteen digit number is probably a timestamp.

    All 9 Gizlets here work in your browser: what you give them stays on this device.

    Which one you need

    JSON is on one line or will not parse, and you need to see why
    JSON Formatter
    Records have to move between JSON and CSV
    JSON and CSV Converter
    A CSV export should be read as a table, or its quoting tidied
    CSV Viewer
    A token from an Authorization header needs reading
    JWT Decoder
    Text or a small file has to go into Base64, or come back out of it
    Base64 Encode & Decode
    A string has to be safe inside a URL, or a URL is full of % escapes
    URL Encode & Decode
    A Unix timestamp has to become a date, or a date a timestamp
    Timestamp Converter
    You need fresh identifiers, or want to know what a UUID contains
    UUID Generator
    A download has a published checksum to compare against
    File Hash Generator

    Every Developer Gizlet

    1. 005JSON FormatterFormat, validate, and read JSON with a clearer structure.Local
    2. 025URL Encode & DecodePercent-encode a string, or read one back.Local
    3. 026Base64 Encode & DecodeMove between plain text, a small file, and Base64.Local
    4. 027JWT DecoderRead a token's header and claims without verifying it.Local
    5. 028File Hash GeneratorCheck a download is the file it claims to be.Local
    6. 029JSON and CSV ConverterMove flat records between JSON and CSV in either direction.Local
    7. 030CSV ViewerRead a delimited file as a table, and tidy its quoting.Local
    8. 031Timestamp ConverterRead a Unix timestamp as a date, and the other way round.Local
    9. 032UUID GeneratorProduce identifiers from your browser's own randomness.Local