UUID Generator

Generate random UUID v4 identifiers, one at a time or in batches, with the browser's crypto API.

Local processing: your data is processed in your browser and never sent to Numelto or any external service.

    How they're generated

    It uses crypto.randomUUID(), the browser's native function for generating unique identifiers with cryptographically secure randomness — not Math.random(), which isn't meant for this.

    Privacy

    The generation happens entirely in your browser. There's no backend behind it — the UUIDs aren't stored or sent anywhere.

    When to use a UUID v4

    A UUID has the format 8-4-4-4-12 hexadecimal characters (3f2b…, for example).

    • Unique identifiers in databases with no coordination between systems.
    • Unpredictable file names or tokens (for secrets, use a dedicated library).
    • Tests and sample data.

    Which UUID version it generates

    It generates UUID v4 identifiers, the most common version: built from random numbers (not from the clock or the device's network address), so they reveal nothing about when or where they were generated.

    Frequently asked questions

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