UUID Generator
Cryptographically random v4 UUIDs — generated in your browser
UUID Generator — Complete Guide & Instructions
MakeCard UUID Generator produces version-4 UUIDs — the standard 36-character random identifiers used across databases, APIs and software. Generate anywhere from 1 to 100 in a click; each UUID uses the browser's cryptographically secure random source (crypto.randomUUID with a getRandomValues fallback), so every value is genuinely unpredictable. Copy a single ID or the whole batch with dedicated buttons — no sign-up, no server, no collisions worth worrying about.
How to Use UUID Generator
- 1 Set "How many" to the number of UUIDs you need — between 1 and 100.
- 2 Click "Generate" — five fresh UUIDs already load when the page opens.
- 3 Press "Copy" beside any single UUID to copy just that value.
- 4 Or press "Copy all" to copy the whole list, one UUID per line, into your clipboard.
Key Features & Capabilities
- True random v4 UUIDs using crypto.randomUUID — the browser's CSPRNG.
- Bulk generation of up to 100 UUIDs in a single click.
- Per-UUID copy button plus a one-click copy-all.
- getRandomValues fallback for browsers without randomUUID.
- Standard 36-char format: xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx.
- Fresh set on every page load — nothing reused or stored.
Supported Formats & Specifications
| Parameter | Specification |
|---|---|
| Version | UUID v4 (random) — RFC 4122 layout |
| Randomness | crypto.randomUUID / getRandomValues (CSPRNG) |
| Batch size | 1–100 per generation |
| Format | 36 characters — 8-4-4-4-12 hex groups |
| Collision risk | Negligible — 122 random bits per UUID |
Practical Everyday Use Cases
- Generating primary keys for database rows and API resources.
- Creating unique filenames for uploads, exports and temp files.
- Seeding test data with realistic identifiers.
- Tagging idempotency keys for payment or form submissions.
- Producing session, transaction or correlation IDs during development.
Pro Tips for Best Results
- UUID v4 is random and unguessable — ideal where IDs must not be enumerable or predictable.
- Generate a few extra — once copied, the list is yours; regenerating replaces it.
- Store UUIDs as text/binary in the database, not integers — they are 128-bit values.
- For sortable IDs consider ULIDs or UUID v7 elsewhere — v4 ordering is random.
Common Problems & Solutions
The tool emits the standard lowercase form — run the list through a text-case tool or uppercase it in your editor.
UUIDs are generated fresh per load and never stored — always copy them before leaving the page.
Genuine v4 collisions are astronomically unlikely; near-identical prefixes are normal since only some sections differ.
Privacy & Security
100% Client-Side Execution
UUIDs are generated entirely in your browser by the crypto API — none are sent to a server, logged or retained.
Frequently Asked Questions
Everything you need to know about using UUID Generator
A UUID (Universally Unique Identifier) is a 128-bit ID that can be generated anywhere without coordination — used for database keys, filenames, session IDs, API resources and anywhere a guaranteed-unique label is needed.
Effectively yes — a v4 UUID has 122 random bits, so the chance of a collision is about 1 in 2.7 quintillion per pair. For practical purposes they never repeat.
They are the same thing — GUID is simply Microsoft's name for a UUID. The format generated here works in .NET, Java, Python, MySQL, Postgres and everywhere else.
Yes — they come from the browser's cryptographically secure random source, the same class of generator used by server-side libraries.
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