Free UUID & GUID Generator (v1–v7) – Online & Secure

Free UUID & GUID Generator — create v1, v2, v3, v4, v5, v6, v7 identifiers online securely in your browser. This tool runs entirely client-side, ensuring 100% privacy: no data is sent or stored on any server. You can generate single or bulk UUIDs (up to 1000 at once), copy them individually or in one click, and export results for immediate use in apps, APIs, databases, or test data workflows.

v4 is best for most apps. v3/v5 require namespace + name.
Enter a number between 1 and 1000.
Try the DNS namespace: 6ba7b810-9dad-11d1-80b4-00c04fd430c8
Generated UUIDs
    No UUIDs yet — choose options and click Generate.
    Copied to clipboard

    Frequently Asked Questions

    A UUID is a Universally Unique Identifier: a 128-bit value used to label data across systems without a central authority. The standard text form is 8-4-4-4-12 hexadecimal characters (e.g., 123e4567-e89b-12d3-a456-426614174000). Also called a GUID (Globally Unique Identifier) in Microsoft/.NET environments.

    Supported: v1 (timestamp + random node), v2 (DCE security, simulated), v3 (namespace + MD5), v4 (cryptographically random), v5 (namespace + SHA-1), v6 (v1 timestamp reordered to sort by time), v7 (Unix millisecond time + randomness). Use v4 for most cases; choose v3/v5 for deterministic, name-based IDs; consider v6/v7 when lexicographic sort by creation time matters.

    Yes. Generation happens entirely in your browser using secure randomness (crypto.getRandomValues), with SHA-1 (Web Crypto) or MD5 computed locally for name-based UUIDs. No network requests are made.

    Yes. Set the amount in the “How many?” field (up to 1000 per batch) and generate instantly. Ideal for test data or bulk workflows.

    Click “Copy” beside any UUID to copy a single value, or use “Copy All” to copy the full list. If available, the Download button saves a .txt file.

    Namespace UUIDs are used by v3 and v5 to create deterministic IDs from (namespace UUID + name string). Common namespaces include DNS (6ba7b810-9dad-11d1-80b4-00c04fd430c8) and URL (6ba7b811-9dad-11d1-80b4-00c04fd430c8).

    v1, v3, v4, v5, v6 and v7 follow the RFC 9562 layout (version and variant bits, timestamp fields). v1/v6 use a random node instead of your MAC address, which the RFC allows. v2 (DCE Security) is simulated: it is a v1 value with the version digit changed. For strict spec compliance or regulated environments, prefer well-reviewed libraries in your target language.

    Everywhere—database primary keys, object IDs in APIs and microservices, event/request tracing, user/session tokens (non-secret), IoT/device IDs, container images, and licensing systems.

    V4 provides ~122 bits of randomness. Collisions are astronomically unlikely—on the order of needing around 2×10^18 random UUIDs for a 50% chance. For typical apps, treat collisions as practically impossible.

    The canonical form is lowercase hex with hyphens, but many systems accept uppercase and/or no-hyphen forms. Convert formats as needed—values remain the same.

    v6 and v7 put the timestamp first, so sorting them as text follows creation time (v7 to the millisecond). v1 stores the low time bits first, so it does not sort as text even though it contains a timestamp. Use v6 or v7 when order-by-ID should reflect recency.