RFC 9562 · SHA-1 · DETERMINISTIC

UUID v5 Generator

Genera deterministic UUID v5 identifiers da a namespace e name using SHA-1. Test reproducibility, inspect UTF-8 input bytes, compare RFC vectors e generate UUIDs in bulk direttamente nel browser.

Browser-only: Namespace and name values are processed locally.

1. Choose Namespace

Namespace scopes your names

Selected Namespace DNS

Namespace UUID 6ba7b810-9dad-11d1-80b4-00c04fd430c8

2. Enter Name

Exact bytes are hashed

Names: 0 Characters: 0 UTF-8 Bytes: 0

UUID Format

RFC v5 Test Vector DNS + www.example.com 2ed6657d-e927-568b-95e1-2665a8aea6a2

UUID v5 Results

Generated 0

Unique UUIDs 0

Duplicates 0

Deterministic Yes

Reproducibility Check

Can this UUID be recreated?

Namespace —

Name —

UTF-8 Bytes —

SHA-1 —

Why Exact Input Matters

UUID v5 hashes bytes, not meaning

Input A example.com

≠

Input B example.com/

These two names are different byte sequences. UUID v5 does not silently remove spaces, change letter case or normalize URLs. Establish a canonical naming rule before sharing UUIDs between systems.

Che cos'è UUID v5?

UUID v5 è un deterministic, name-based UUID formato. Instead ofgenerating a casuale identifier, it combines a namespace UUID witha name e applies SHA-1 to the resulting byte sequence.

The first 128 bits of the SHA-1 digest are adapted in UUID formatoby setting the versione bits to 5 e the RFC variante bits.Because the process is deterministic, the same namespace e exactname always produce the same UUID.

UUID v5 Nomespaces

DNS:Domain names such as example.com
URL:URLs e URL-like identifiers
OID:Object identifiers
X.500:Distinguished names
Custom:Application-controlled namespace UUIDs

When UUID v5 Is Useful

Stable IDs per URLs e domains
Deterministic data imports
Idempotent ETL operations
Cross-system record matching
Stable test fixtures
Nomespaced cache o resource identifiers

UUID v5 vs UUID v4

UUID v4 is primarily casuale e is useful quando a new unpredictableidentifier is required. UUID v5 is deterministic e is useful whenan identifier must be reproducible da known input.

UUID v5 vs UUID v3

UUID v3 e UUID v5 both use a namespace e name. UUID v3 uses MD5,while UUID v5 uses SHA-1. For new deterministic UUID implementations,UUID v5 is generally the preferred choice quando interoperability withthe UUID v5 standard is required.

Frequently Asked Questions

UUID v5 è un deterministic, name-based UUID formato. It combines a namespace UUID e a name string, hashes them using SHA-1 e converts the result in a UUID con versione 5 e the RFC variante.

Sì. When the namespace UUID e name bytes are exactly the same, a compliant UUID v5 implementation produces the same UUID.

A namespace è un UUID that scopes the name being hashed. Standard namespaces include DNS, URL, OID e X.500. Applications can also use their own custom namespace UUID.

No. UUID v5 hashes the supplied name bytes. Differences such as uppercase letters, whitespace, URL trailing slashes o Unicode representations can produce different UUIDs.

No. UUID v5 is deterministic rather than casuale. The same namespace e name produce the same UUID.

No. UUID v5 is designed per deterministic identifiers, not passwords, authentication tokens, secrets o digital signatures.

Sì. Enter one name per line e the tool generates a deterministic UUID v5 per each name using the selected namespace.

Both are deterministic namespace-based UUIDs, but UUID v3 uses MD5 while UUID v5 uses SHA-1 per the UUID generation algorithm.

No. SHA-1 generation e UUID formatoting are performed locally in your browser.