Free Online UUID/GUID Generator, Validator & Decoder
UUIDs (Universally Unique Identifiers), also known as GUIDs (Globally Unique Identifiers),
are 128-bit identifiers that are unique across time and space. Our free UUID tool generates v1, v3, v4, v5, and v7 UUIDs,
validates existing UUIDs, and decodes them to reveal version, variant, and embedded timestamps — all in your browser.
Key Features
- 6 UUID Versions — Generate v1 (time-based), v3 (MD5 namespace), v4 (random), v5 (SHA-1 namespace), v7 (Unix epoch time), and Nil UUIDs.
- Namespace Support — For v3 and v5, choose from DNS, URL, OID, X500, or enter a custom namespace UUID.
- Format Options — Uppercase, remove dashes, or add braces to match your project's style.
- Bulk Generation — Generate up to 1,000 UUIDs at once with one click.
- Validate & Decode — Paste any UUID to check validity, detect the version, variant, and extract timestamps from v1/v7.
- Export Options — Copy all, copy as JSON array, or download as a .txt file.
- Client-Side Processing — Everything runs locally in your browser. Your data never leaves your device.
SimplyUtils vs Other UUID Generators: Feature Comparison
Looking for an alternative to uuidgenerator.net, uuidtools.com, or guidgenerator.com? Here's how SimplyUtils compares
to the most popular online UUID generators in terms of features:
Feature
SimplyUtils
uuidgenerator.net
uuidtools.com
guidgenerator.com
Completely Free
✓
✓
✓
✓
UUID v1 (Time-based)
✓
✓
✓
✗
UUID v3 (MD5 Namespace)
✓
✓
✓
✗
UUID v4 (Random)
✓
✓
✓
✓
UUID v5 (SHA-1 Namespace)
✓
✓
✓
✗
UUID v7 (Unix Epoch Time)
✓
✗
✗
✗
Nil UUID
✓
✓
✗
✗
UUID Validator
✓
✗
✓
✗
Version & Variant Detection
✓
✗
Partial
✗
Timestamp Extraction
✓
✗
✓
✗
Format Options (Uppercase/Dashes/Braces)
✓
Limited
Limited
✓
Bulk Generation (up to 1,000)
✓
✓
✓
✓
Copy as JSON Array
✓
✗
✗
✗
Download as .txt
✓
✗
✗
✗
Client-Side Processing
✓
✗
✗
✓
Dark Mode
✓
✗
✗
Why Choose SimplyUtils Over uuidgenerator.net, uuidtools.com, or guidgenerator.com?
While uuidgenerator.net, uuidtools.com, and guidgenerator.com each offer
some UUID features, no single competitor matches what SimplyUtils provides:
- v7 support that others lack — UUID v7 is the newest standard, ideal for time-sortable database keys. uuidgenerator.net, uuidtools.com, and guidgenerator.com don't support it yet. SimplyUtils does.
- Generate + Validate in one tool — uuidgenerator.net only generates UUIDs but can't validate or decode them. guidgenerator.com is the same. SimplyUtils combines both in a tabbed interface.
- Timestamp extraction — Paste a v1 or v7 UUID and instantly see when it was created. Only uuidtools.com offers something similar, but SimplyUtils also handles v7 timestamps.
- Developer-friendly export — Copy as JSON array or download as .txt — features none of the competitors offer. Perfect for seeding databases or test fixtures.
- Full format control — Uppercase, remove dashes, add braces — all toggleable. guidgenerator.com has some options, but uuidgenerator.net and uuidtools.com give you limited control.
- Privacy-first — SimplyUtils generates UUIDs entirely in your browser using the Web Crypto API. uuidgenerator.net and uuidtools.com generate UUIDs server-side, meaning your requests hit their servers.
Understanding UUID Versions
- UUID v1 (Time-based) — Uses the current timestamp and a node identifier. Reveals creation time, useful when you need chronological ordering. Be aware it can expose timing information.
- UUID v3 (MD5 Namespace) — Deterministic: the same namespace + name always produces the same UUID. Uses MD5 hashing. Good for creating consistent IDs from known inputs.
- UUID v4 (Random) — The most popular version. Generated from cryptographically secure random numbers. Best for general-purpose unique identifiers where ordering doesn't matter.
- UUID v5 (SHA-1 Namespace) — Like v3 but uses SHA-1 instead of MD5. Preferred over v3 for new projects because SHA-1 has better collision resistance.
- UUID v7 (Unix Epoch Time) — The newest standard (RFC 9562). Embeds a Unix timestamp in the first 48 bits, making UUIDs sortable by creation time. Ideal for database primary keys because they're time-ordered, reducing index fragmentation.
- Nil UUID — All zeros (00000000-0000-0000-0000-000000000000). Used as a placeholder or "not set" value in systems that require a UUID field.
Which UUID Version Should You Use?
- Database primary keys — Use v7. Time-sorted UUIDs improve index performance and give you creation timestamps for free.
- General unique IDs — Use v4. Pure randomness with no embedded info. The default choice for most apps.
- Deterministic IDs from known data — Use v5 (or v3). Hash a namespace + name to always get the same UUID for the same input.
- Legacy systems needing timestamps — Use v1. Embeds creation time, but consider v7 for new projects.
Common Use Cases
- Database Primary Keys — Unique IDs that work across distributed systems without coordination.
- API Resources — Identify resources without exposing sequential IDs or record counts.
- Distributed Systems — Generate IDs on any node without a central authority.
- Session Tokens — Create unique, unguessable session identifiers.
- File Names — Prevent naming collisions when storing user uploads.
- Content Addressing — Use v5 to create deterministic IDs from content hashes.
UUID Format Explained
A UUID is a 128-bit number displayed as 32 hexadecimal digits in the pattern 8-4-4-4-12:
550e8400-e29b-41d4-a716-446655440000
The 13th character indicates the version (4 in this example), and the 17th character indicates the variant (a, b, 8, or 9 for RFC 4122).
UUID vs Auto-Increment IDs
- Distributed generation — UUIDs don't need a central server to assign IDs.
- Security — Can't guess other records by incrementing/decrementing.
- Merge-friendly — No conflicts when combining data from multiple sources.
- Trade-offs — UUIDs are larger (36 chars vs 8-10 digits) and less human-readable. v7 mitigates the index performance concern by being time-sorted.
Whether you need to generate UUIDs in bulk, validate existing ones, or decode timestamps from v1/v7 UUIDs,
SimplyUtils is the most complete free UUID tool online. Try it above — select a version, configure your format, and generate.