UUID / GUID Generator
Generate random UUID v4 or time-ordered UUID v7 identifiers in bulk – up to 1,000 at once, with uppercase, braces and no-hyphen options. Uses your browser's secure random generator.
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- ✓ 100% free
- ✓ No sign-up
- ✓ No limits
- 🔒 Files never leave your device
How to: UUID Generator
- Choose the UUID version and how many.
- Pick a format: hyphens, uppercase or braces.
- Copy all or download the list.
A UUID (universally unique identifier) is a 128-bit value such as 3f2b8c1e-9d4a-4f6b-a2c7-1e5d9b0f7a42 that can be created anywhere without coordination and still be unique. This generator creates version 4 (random) and version 7 (time-ordered) UUIDs using the browser's cryptographically secure random generator.
Common uses
- Create primary keys for databases and distributed systems.
- Generate IDs for test data, fixtures and API mocks.
- Create unique file names, session IDs and correlation IDs for logs.
- Produce GUIDs for Windows, .NET and COM registrations.
Tips for best results
- Prefer UUID v7 for database primary keys – they sort by creation time, which keeps indexes efficient.
- Store UUIDs as native UUID or 16-byte binary types rather than 36-character strings when possible.
- Do not use UUIDs as secrets or password reset tokens; use a dedicated random token.
- Use uppercase with braces for Windows registry and Visual Studio project files.
v4 or v7?
Version 4 UUIDs are completely random, which is ideal when you do not want identifiers to reveal anything. Version 7, standardised in RFC 9562 in 2024, starts with a 48-bit Unix timestamp in milliseconds followed by random bits. Records created later get larger IDs, so B-tree indexes in PostgreSQL, MySQL and SQL Server stay compact, and you can roughly tell when a record was created.
Format variations
The canonical form is 32 lowercase hexadecimal digits in groups of 8-4-4-4-12. Some systems want them without hyphens (32 characters), in uppercase, or wrapped in braces. The nil UUID, all zeros, is used as a placeholder for “no value”.
Why use FreePDF for UUID Generator?
| FreePDF | Typical upload-based sites | |
|---|---|---|
| What you type is sent to a server | No – stays in your browser | Often |
| Sign-up required | Never | Often for bigger jobs |
| Hourly / daily task limits | None | Common on free plans |
| Works offline after loading | Yes, for most tools | No |
Frequently asked questions
Are the UUIDs really unique
Version 4 UUIDs have 122 random bits. Generating a billion per second for about 85 years would give a 50% chance of a single collision, so in practice they are unique.
Is a GUID the same as a UUID
Yes. GUID is Microsoft's name for the same 128-bit identifier; Windows often writes them in uppercase inside braces.
Is UUID Generator really free?
Yes. Every tool on FreePDF is 100% free with no file limits, no sign-up and no watermarks. The site is supported by unobtrusive ads.
Are my files uploaded to a server?
No. FreePDF processes your files directly in your browser using JavaScript. Your documents never leave your device, so they stay completely private.
Does it work on mobile?
Yes. FreePDF works in any modern browser on Android, iPhone, iPad, Windows, Mac and Linux.