ToolVaults

UUID Generator (v4, v7, Nil)

Generate cryptographically-strong UUIDs in bulk. Supports v4 (random), v7 (time-ordered), and the nil UUID. Formatting options included.

Runs 100% in your browser — nothing is uploaded.

    How to use

    1. 1
      Pick a version

      v4 = pure random. v7 = timestamp-prefixed, sorts chronologically — the modern default for database keys.

    2. 2
      Choose count

      Generate 1 or up to 100 at once. Bulk mode outputs one per line, ready to paste into a script.

    3. 3
      Format the output

      Toggle uppercase, remove dashes, or wrap in braces to match your language conventions.

    4. 4
      Copy and use

      Copy to clipboard, or generate a fresh batch for each row you need.

    Examples

    One v4 UUID
    Input
    Version v4 · count 1 · lowercase
    Output
    3f9d2c7a-4b1e-4c58-9f21-8a5e7d0c3b4f
    Cryptographically random. 122 bits of entropy.
    One v7 UUID
    Input
    Version v7 · count 1
    Output
    01926f3a-8b12-7c58-9f21-8a5e7d0c3b4f
    The first ~48 bits encode a millisecond timestamp, so this UUID sorts naturally by creation time.
    Bulk (5 · uppercase · no dashes)
    Input
    Version v4 · count 5 · uppercase · no dashes
    Output
    3F9D2C7A4B1E4C589F218A5E7D0C3B4F
5A1B4E9C7F2D48E19E123456ABCDEF01
...
    Perfect for seeding a test table or generating batch IDs.

    Frequently asked

    What is the difference between v4 and v7?

    v4 UUIDs are entirely random and unordered — great for uniqueness, terrible for database indexing. v7 UUIDs prepend a millisecond timestamp so they sort chronologically, making them much better as primary keys.

    Are these UUIDs cryptographically random?

    Yes. We use the browser Web Crypto API (crypto.randomUUID and crypto.getRandomValues) — the same source of randomness used for HTTPS handshakes.

    Can I generate more than 100 at once?

    The UI caps at 100 to keep the page snappy. If you need thousands, wire the same logic into your own script or hit the (upcoming) API.

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