How does this GUID generator work?

GUIDs are generated entirely in the browser. When available, the Web Crypto API is used; otherwise a cryptographic fallback is used. No server logging happens.

Yes. The tool is permanently free, ad-free and usable without login.

Which GUID version is generated?

The tool generates RFC 4122 compliant UUIDv4 strings with random bits.

Can I use the GUIDs in databases or scripts?

Yes. GUIDs can be copied directly into SQL, JSON, CSV or other data pipelines.

GUID Generator | UUIDv4 Strings for Developers

Current GUID

Useful for API keys, test data or quick references.

a7e21431-8e3e-4d86-aba4-20006ad72c16

Batch Generation

Create lists for seed data, CSV exports, QA or scripts.

Why UUIDv4?

Avoid collisions: 122 random bits provide 5.3e36 combinations.
Independent from databases: No sequences or central ID management needed.
Standards-compliant: RFC 4122 compatible for .NET, Node.js, Go, Java and more.

Use Cases

APIs & Auth: Request IDs, API keys, refresh tokens.
Microservices: Service-übergreifende IDs ohne Coordinator.
Data imports: Bulk seeds for SQL, MongoDB or Firestore.

Quick guide

Generate a single GUID and copy it, useful for UI or API tests.
Enter the required amount in the batch field and click generate.
Use copy all to export the list line by line, for example for CSV or SQL IN clauses.
Regenerate when needed. Every list is independent and easy to move via copy and paste.

All calculations run client-side with Web Crypto. GUIDs are not stored or tracked.

What is inside a GUID?

A UUIDv4 consists of five blocks of hexadecimal characters (8-4-4-4-12). Bits 48–51 define the version, bits 64–65 define the variant.

Format

xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx

Version

v4 (Random). Bits 12–15 are always 0100.

Variant

RFC 4122 (Leach-Salz). Bits 16–17 beginnen mit 10.

Best Practices

Store as text: GUIDs are hexadecimal strings. Use CHAR(36) or UUID columns.
Shorten for logs: Use the first 8 characters as a short ID in the interface.
Do not encode meaning: IDs should not contain business information, which helps protect privacy.
Document batch versions: Store lists in the repo or setup script to keep environments reproducible.

Frequently Asked Questions

How secure are the GUIDs?

The tool uses the Web Crypto API when available (crypto.randomUUID). If it is unavailable, a cryptographic fallback provides random bits. Collision probability is practically zero.

Are my inputs stored?

No. Everything happens locally in the browser, which is useful for sensitive test data or secret tokens.

Can I generate other UUID versions?

The focus is UUIDv4. For name-based UUIDv5 or time-based UUIDv1, use specialized libraries such as uuid for Node.js. This tool stays intentionally focused.

What is the best way to copy large batches?

Use copy all to get a line-by-line list. You can paste it directly into CSV, JSON arrays or SQL scripts.