Free UUID Generator
Universally Unique Identifiers are the standard way to mint collision-free IDs for databases, APIs, and distributed systems. The UUID Generator produces random v4 UUIDs via crypto.randomUUID() and time-ordered v7 UUIDs — which sort by creation time and index far better in databases — in batches up to 100, with uppercase, brace, and hyphen-free formatting.
v7 sorts by creation time — great for database keys.
How to Use the UUID Generator
- Choose the UUID version — v4 random, v7 time-ordered, or nil.
- Set the quantity and any formatting options.
- Click Generate UUIDs.
- Copy all or download the list.
Features
v4, v7, and nil UUIDs; up to 100 per batch; time-ordered v7; uppercase/braces/no-hyphen formatting; copy and download.
Benefits & Use Cases
Generate primary keys, request IDs, idempotency keys, test fixtures, or correlation IDs for logs and traces.
Tips
Prefer v7 for database primary keys — sequential values keep indexes compact and inserts fast. Use v4 when you need pure randomness with no timestamp embedded.
Frequently Asked Questions
What is a UUID?
A 128-bit identifier written as 32 hex digits in five groups (like 550e8400-e29b-41d4-a716-446655440000). Random UUIDs are practically guaranteed unique without coordination.
v4 vs v7 — which should I use?
v4 for pure random IDs; v7 when IDs are database keys — its timestamp prefix makes them roughly time-ordered, which keeps indexes efficient.
Can UUIDs collide?
With 122 random bits, you would need to generate billions per second for a century to expect one collision. For all practical purposes: no.
What is a nil UUID?
The all-zeros UUID (00000000-0000-0000-0000-000000000000), used as a null/empty placeholder in some systems and tests.
Related Tools
Secure Token Generator
Generate secure random tokens free with NToolHub. API keys and session IDs in hex, Base64 or URL-safe form — 100% in your browser, nothing uploaded.
Open tool →Random String Generator
Generate random strings free with NToolHub. Custom charsets, hex mode and bulk output with secure randomness — 100% in your browser, nothing uploaded.
Open tool →CSRF Token Generator
Generate CSRF tokens free with NToolHub. Cryptographically secure hex tokens for form protection, 16–64 bytes — 100% in your browser, nothing uploaded.
Open tool →JWT Generator
Generate unsigned test JWTs instantly with NToolHub’s free tool. Custom header and payload, live decode preview — test-only, private.
Open tool →Random Number Generator
Generate truly random numbers free with NToolHub. Set any range, pick unique or sorted results, and copy instantly. Secure, fast, no sign-up.
Open tool →