UUID Version 3 Generator
UUIDv3 • MD5 Hashed Namespace & Name
00000000-0000-0000-0000-000000000000
Enclose:
Generate Bulk UUIDs
0 msReady
Max 5,000
Formatting & Structure
Ready
No batch active1-click copy available on each row
Deterministic Name-Based•RFC 9562 Section 5.3 / RFC 4122
UUID Version 3 Technical Specification (MD5 Namespace)
UUIDv3 is a deterministic namespace-based identifier algorithm that hashes input strings using the MD5 digest algorithm. While superseded by SHA-1 (v5), it remains widely supported for backwards compatibility with legacy systems.
Bitfield Layout & Binary Structure
Detailed 128-bit byte distribution according to RFC standards.
| Field Name | Bit Range | Purpose & Description |
|---|---|---|
| md5_hash[0..47] | 48 bits (0-47) | First 48 bits of MD5 digest. |
| ver | 4 bits (48-51) | Constant binary value 0011 (identifies Version 3). |
| md5_hash[52..63] | 12 bits (52-63) | Bits 52 to 63 of MD5 digest. |
| var | 2 bits (64-65) | Constant binary value 10 (RFC standard variant). |
| md5_hash[66..127] | 62 bits (66-127) | Bits 66 to 127 of MD5 digest. |
✓
Advantages & Strengths
- •Deterministic output across platforms and languages.
- •Slightly faster hashing speed than SHA-1 on low-powered processors.
!
Considerations & Trade-offs
- •MD5 has known cryptographic collision vulnerabilities; new designs should always choose UUIDv5.
Best Recommended For
- →Maintaining backwards compatibility with existing legacy UUIDv3 databases.
When to Avoid
- ✕All new software architectures (use Version 5 instead).
Code Implementation Examples
Python Standard LibraryPython
import uuid
id = uuid.uuid3(uuid.NAMESPACE_DNS, 'bulkuuidgenerator.com')
print(id)Frequently Asked Questions
Why should new systems prefer UUIDv5 over UUIDv3?▼
Both versions operate identically from a developer interface standpoint, but UUIDv5 uses SHA-1 instead of MD5. SHA-1 has a larger digest state and is substantially more collision-resistant.