GUIDs & UUIDs Generator
Generate GUIDs / UUIDs (v4, v6 and v7) with custom formatting, encoding and one-click copy.
Do it all online inside your browser for free. No API calls needed. No data sent anywhere.
What is a GUID / UUID?
A GUID (Globally Unique Identifier), also called a UUID (Universally Unique Identifier), is a 128-bit identifier standardized by RFC 4122 for v4 and RFC 9562 for newer versions. It is designed to be globally unique, meaning no two GUIDs / UUIDs are expected to ever collide. Even when generated on different machines or at large scale.
GUIDs / UUIDs are widely used in databases, APIs, cloud services, distributed systems and software applications where reliable unique identifiers are essential. Their extremely low collision probability allows developers to create unique IDs without relying on a central authority or database lookup. Making them ideal for fast and scalable applications.
Universally Unique IDentifier (UUID) / Globally Unique IDentifier (GUID) - Wikipedia
GUID - Microsoft.com
GUID / UUID Versions: v4, v6 and v7
There are several GUID / UUID versions, but the most relevant and widely used today are v4, v6, and v7. These versions are secure, modern, and suitable for large-scale distributed systems.
Comparison of UUID / GUID Versions
| Version | Type | Deterministic? | Sortable? | Secure? | Typical Use | RFC | Notes |
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| v1 | Time + MAC | No | Yes | MAC leak | Distributed systems | RFC 4122 | Includes timestamp + MAC address. Ordered but exposes hardware info. |
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| v2 | DCE Security (UID/GID) | No | Partial | Leaks IDs | Legacy DCE systems | RFC 4122 | Embeds POSIX UID/GID + MAC address. Rarely supported and considered obsolete. |
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| v3 | Name (MD5) | Yes | No | MD5 | Namespace-based IDs | RFC 4122 | Deterministic, but MD5 is cryptographically broken. |
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| v4 | Random | No | No | Yes | General purpose (Recommended) | RFC 4122 | Pure randomness (122 random bits). Extremely low collision probability. |
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| v5 | Name (SHA-1) | Yes | No | SHA-1 | Stable API IDs | RFC 4122 | Deterministic like v3 but uses SHA-1, which is no longer fully secure. |
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| v6 | Ordered time v1 | No | Yes | Yes | Database indexing | RFC 9562 | Improved v1 format with sortable structure + privacy-safe design. |
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| v7 | Timestamp + randomness | No | Yes | Yes | Latest most modern | RFC 9562 | Combines millisecond timestamps with strong randomness. Ideal for distributed systems. |
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| v8 | Custom / User-defined | Depends | Depends | Custom | Experimental, app-specific | RFC 9562 | Flexible GUID / UUID layout reserved for application-defined use. Not recommended for generic scenarios. |
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Supported GUID / UUID versions by this generator
This generator intentionally supports only secure, modern GUID / UUID versions — v4, v6, and v7. Older or deprecated versions such as v1, v2, v3, v5 and v8 are not supported because they rely on outdated hashing algorithms, expose hardware or user identifiers, lack modern security guarantees or are intended for custom implementations without standardized structure.
Disclaimer: All information is provided for general educational and technical reference only. While we aim to keep the content accurate, current and aligned with published standards. No guarantees are made regarding completeness, correctness or suitability for any specific use case.
GUID / UUID specifications, RFCs, best practices, security guidance, database behavior and ecosystem conventions (including cloud platforms and third-party identifier formats) may change over time or differ by implementation. Examples, recommendations, and comparisons are illustrative and may not apply universally.
This content should not be considered legal, security, compliance or architectural advice. Before making critical design, security, or production decisions, always consult the latest official standards and documentation (such as RFC 4122, RFC 9562, and vendor-specific references).
Always evaluate behavior in your own environment.