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UUID Generator

UUID Generator

Professional UUID generation, validation, and analysis with support for all UUID versions.

Generator Settings

Timestamp-based with MAC address

Name-based using MD5 hash

Random or pseudo-random

Name-based using SHA-1 hash

    Examples

    Single UUID version 4

    Output
    550e8400-e29b-41d4-a716-446655440000

    A random 128-bit identifier in the canonical 8-4-4-12 hex layout, ready to use as a database key or resource ID.

    Bulk generate (3)

    Input
    Version: v4  ·  Count: 3
    Output
    a1b2c3d4-e5f6-7890-abcd-ef1234567890
01234567-89ab-cdef-0123-456789abcdef
fedcba98-7654-3210-fedc-ba9876543210

    Generate many at once to seed a test database or fixture — every value is independently unique.

    Uppercase, no hyphens

    Input
    Version: v4  ·  Uppercase  ·  No hyphens
    Output
    A3F2B8C14D5E6F7A8B9C0D1E2F3A4B5C

    Match a storage or code convention that wants a flat, uppercase 32-character hex string.

    About this tool

    A UUID (Universally Unique Identifier, also called a GUID) is a 128-bit value designed to be unique across space and time without any central coordination. That property makes UUIDs ideal as database primary keys, session and request identifiers, file names, and API resource IDs — especially in distributed systems where two nodes must generate non-colliding IDs independently. The most common variant, version 4, is almost entirely random, which is why collisions are, for practical purposes, impossible.

    This generator produces RFC 9562-compliant UUIDs using the browser's cryptographically strong Web Crypto random number generator. Create one identifier on demand or bulk-generate hundreds for seeding test data, and copy them in the exact casing and formatting your codebase expects. All generation is local — no identifier is ever sent to a server.

    How to use

    1. Generate a UUID

      Click generate to produce a fresh, random version-4 UUID.

    2. Bulk generate

      Set a count to create many UUIDs at once for seeding databases or test fixtures.

    3. Adjust the format

      Toggle options like uppercase or hyphenation to match your storage or code conventions.

    4. Copy the result

      Copy a single UUID or the whole batch to your clipboard.

    Use cases

    Database primary keys

    Give each new row a unique ID without a central counter or a round-trip to the server.

    Distributed systems

    Two nodes can generate IDs independently with no risk of collision and no coordination.

    Session & request IDs

    Tag requests, traces, and sessions for correlation across logs without a shared sequence.

    Test fixtures & mock data

    Bulk-generate hundreds of realistic, unique keys when seeding databases or sample data.

    UUID at a glance

    AspectDetail
    Length128 bits, shown as 36 characters (32 hex digits + 4 hyphens)
    Version 4Random — the default, collision-resistant general-purpose ID
    Format8-4-4-4-12 hexadecimal groups, e.g. 550e8400-e29b-41d4-a716-446655440000
    RandomnessWeb Crypto CSPRNG — cryptographically strong

    Generation is fully client-side and RFC 9562-compliant.

    Common mistakes

    Mistake:Treating a UUID as a secret or password.

    Fix:UUID v4 is random but not a security token — use a dedicated generator for secrets and session tokens.

    Mistake:Truncating a UUID to shorten it.

    Fix:Cutting characters destroys the collision guarantees. Use the full UUID, or pick an ID scheme designed to be short.

    Mistake:Storing UUIDs as VARCHAR when the DB has a native type.

    Fix:Use the native UUID/GUID type (PostgreSQL uuid, SQL Server UNIQUEIDENTIFIER) for smaller storage and faster indexing.

    Mistake:Assuming UUIDs sort in creation order.

    Fix:v4 UUIDs are random and don't sort chronologically — use v7 (time-ordered) or a created-at column when order matters.

    Frequently asked questions

    Related guides

    How BIP39 Seed Phrases Work (and Why You Must Never Reuse One)

    The entropy-to-words mapping, the checksum, and the security model that makes a 12-word phrase protect an entire cryptocurrency wallet.

    UUID Versions Explained: v1 vs v4 (and Where v7 Fits)

    What the version nibble in a UUID means, how v1 and v4 differ, why v7 is taking over for database keys, and how unlikely a collision really is — with generation tips and format options.

    References & standards

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