UUID Generator
Generate cryptographically secure UUIDs (v4 random or v7 timestamp-ordered) instantly in your browser.
01Why this UUID tool
Unique IDs, your way.
Four reasons backend folks and platform engineers use this tab instead of opening a REPL.
- 01
v4 random or v7 time-ordered
Pick v4 for fully random IDs (the classic default), or v7 for time-ordered IDs that sort naturally and behave well in database indexes.
- 02
Bulk generate up to 500
Need a seed list for test fixtures? Generate 500 in one shot and copy the whole batch in one click.
- 03
Cryptographically secure
Built on crypto.getRandomValues, the same CSPRNG your runtime would use. No collisions in any practical workload.
- 04
All on your device
Generation runs in your browser. The IDs are yours alone: never sent, never logged, never reused.
02How it works
Pick, count, copy.
- Versionv4v7
Step 1Pick a version
v4 is the safe random default. v7 (newer) embeds a timestamp so IDs sort by creation time, which is much friendlier to database indexes.
- Count110100500
Step 2Set how many you need
One ID for a primary key or hundreds for fixtures. Slider runs from 1 to 500.
- CopiedUUIDs8f14e45f-ceea-467a-a4d6-78c310 IDs · per-line ready
Step 3Copy the result
Copy a single value or the entire batch. Paste into your seed file, your config, or your test.
03Use cases
Where UUIDs shine.
Primary keys, request IDs, and fixtures. Anywhere a unique handle belongs.
Primary keys for new rows
Generating IDs client-side so the frontend knows what to render before the round-trip. v7 keeps the index hot.
v7 · 50 keys for a seed migrationRequest IDs for tracing
Tag every request with a UUID so you can correlate logs across services. Pass through headers, attach to spans.
X-Request-Id · per callTest fixtures
Need 100 deterministic-shape IDs for a test? Generate, paste into the fixture file, run.
100 user IDs for unit testsIdempotency keys
POST endpoints with retries need a stable key. Generate one per logical operation so retries don't duplicate.
Stripe-style idempotency keyObject storage filenames
Uploading user files? Use a UUID instead of the user-supplied name to avoid collisions and traversal bugs.
S3 key · safer than user namesFeature flag rollouts
Need a stable random per session? Generate a UUID once, store it in localStorage, hash to a bucket.
Session bucket · stable rollout
04Quick tips
Use UUIDs right.
Four habits that keep IDs doing the right job.
- 01
Prefer v7 for database IDs
v4 IDs are random across the keyspace, which is bad for B-tree indexes. v7 sorts by creation time and keeps index inserts mostly sequential.
- 02
Don't slice off characters
Truncating a UUID raises collision risk fast. If you need a shorter ID, use a different scheme (nanoid, short hash) rather than a chopped UUID.
- 03
Never use as a secret
UUIDs are unpredictable, not unguessable. For auth tokens or API keys, use the password generator or a real key-derivation strategy.
- 04
Compare canonical form
Some systems strip dashes, some uppercase. Normalize to lowercase dashed form before comparing UUIDs across services.
05Questions
UUIDs, plainly answered.
Questions before your first generate. Missing one? contact@wirelogs.com.
01What's the difference between UUID v4 and v7?
v4 is fully random (122 bits of randomness). v7 prefixes the random portion with a millisecond timestamp, so IDs sort by creation time. Both versions are defined in RFC 9562. v7 is gentler on database indexes and easier to debug.
02Are these really unique?
Effectively yes. v4 has 2^122 possible values, so you'd need to generate over a trillion per second for years before a collision is even plausible. v7 adds time to the front, which makes collisions even rarer.
03Can I use a UUID as a security token?
Not as the only line of defense. UUIDs are unguessable in practice, but they're not secrets and shouldn't replace proper authentication tokens. Use the password generator for credentials.
04Are IDs sent to any server?
No. Generation is local, using the browser's crypto.getRandomValues. Wirelogs never sees the values you generate.
05How many can I generate at once?
Up to 500 per batch. Click again for more, since there's no quota.
06Is it free?
Yes. No sign-up, no usage cap, no watermark.
Ready when you are
Generate uniques.
Pick v4 or v7, set the count, copy. Nothing leaves your browser.
- 500per batch
- CSPRNGtruly random
- $0now and always
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