Free UUID Generator
Create random UUID v4 values for test records, prototypes, imports, and development workflows.
Generate UUID v4 values for Java and JavaScript
The output uses the standard UUID text shape with 32 hexadecimal digits and four hyphens. Version 4 UUIDs are random identifiers, so the same values can be stored by Java, JavaScript, Node.js, databases, APIs, spreadsheets, and test fixtures when those systems accept UUID strings.
This browser generator creates random UUID v4 values with the Web Crypto API. It does not run Java code, create database records, find an existing UUID, validate every UUID version, or generate a password. Use the Password Generator for credentials and the Random Number Generator for bounded numbers.
How this tool helps
UUIDs are convenient identifiers when you need values that are unlikely to collide across test data, local prototypes, forms, imports, or temporary records. This generator uses the browser crypto API where available and can create a single value or a small batch for quick copying.
How to use it
- Choose how many UUIDs you need; small batches are easier to review and paste into test fixtures.
- Generate the list and copy either one line or the whole block depending on your workflow.
- Use the values as identifiers, not passwords, because UUIDs are designed for uniqueness rather than account security.
Practical tips
- Keep the hyphenated format when a system expects standard UUID v4 text.
- Do not use a UUID as proof that a user is authorized; treat it as an identifier only.
- For database imports, generate once and keep the list with the sample records so references stay consistent.
FAQ
What version does this create?
It creates random UUID version 4 values using crypto.randomUUID when the browser supports it.
How many can I generate at once?
The page allows 1 to 100 UUIDs so the output remains manageable in the browser.
Are UUIDs secret tokens?
No. They are useful identifiers, but sensitive tokens need purpose-built random secret generation and storage.
Related tools
Generate random GUIDs and UUIDs
A GUID (Globally Unique Identifier) is functionally identical to a UUID (Universally Unique Identifier). Both are 128-bit values formatted as 32 hexadecimal characters with hyphens: 550e8400-e29b-41d4-a716-446655440000. Version 4 (random) GUIDs are the most common for software development.
Use the generator above to create single GUIDs or bulk batches. GUIDs are used for database primary keys, session tokens, file names, and distributed system identifiers. For cryptographic purposes, this browser generator uses crypto.getRandomValues() which provides sufficient randomness for most use cases.