Free online UUID generator (v4 & v1, bulk)

Generate RFC 4122 UUIDs in your browser—up to 500 at once, copy all, optional UPPERCASE and no dashes.

  • No signup
  • Bulk up to 500
  • Copy all
  • Runs locally
About UUIDs (v1 vs v4)

A UUID (Universally Unique Identifier) is a 128-bit ID, often used in APIs and databases. v4 is random and most common; v1 embeds a timestamp (this library does not use a real MAC—fine for non-security uniqueness).

  • Version 4: Random—default for new IDs.
  • Version 1: Time-ordered—useful when sort-by-creation approximates time.

How this tool fits your workflow

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Why developers need a bulk UUID generator

Creating unique identifiers for distributed systems, database records, or API requests is a daily task for developers. Most UUID generators produce one ID at a time, requiring multiple clicks for bulk operations like seeding test databases or generating session tokens for QA environments.

Bulk UUID generation saves time when setting up development environments, creating test fixtures, or initializing distributed systems that need hundreds of pre-generated identifiers. The ability to generate up to 500 UUIDs in one click eliminates repetitive clicking and copy-pasting.

UUID v4 vs v1: choosing the right version

UUID v4 generates completely random 122-bit values with 6 fixed version/variant bits, making it ideal for general-purpose unique identifiers. Use v4 for user IDs, session tokens, database primary keys, and scenarios where you need guaranteed uniqueness without embedded information.

UUID v1 embeds the current timestamp and a node identifier, allowing rough chronological sorting of IDs. This is useful for event logging, time-series databases, and distributed systems where creation order provides value. Browser implementations use random node IDs instead of MAC addresses to protect user privacy.

Common use cases for UUID generation

Database primary keys in distributed systems benefit from UUIDs because they eliminate the need for centralized ID coordination. Unlike auto-increment IDs, UUIDs can be generated independently by any service without conflicts.

API development often requires unique request IDs for tracing, debugging, and distributed logging. Session tokens, file names in object storage, and temporary resource identifiers all benefit from UUID-based naming that guarantees uniqueness across systems and time.

Client-side generation for privacy

Generating UUIDs in your browser means the identifiers never leave your device. This matters when creating IDs for sensitive systems, internal tools, or scenarios where you want to avoid any external service knowing which IDs are being generated.

The UUID library runs entirely in JavaScript with no server communication, making it safe for generating identifiers for customer data, financial systems, healthcare records, or any scenario requiring strict data privacy compliance.

Frequently asked questions

How many UUIDs can I generate at once?
You can generate up to 500 UUIDs in one batch-similar to bulk-focused tools in search results-then copy the whole list.
Are UUIDs generated securely?
IDs come from the established uuid package in your browser context. For cryptographic security guarantees, prefer your platform crypto APIs in production code; this page is ideal for dev/test and quick IDs.
What is the difference between UUID v4 and v1?
v4 is random and most widely used. v1 is time-based and can help approximate creation order. Both follow RFC 4122 string format when dashes are enabled.
Is my data sent to a server?
No. Generation runs locally in your browser. Nothing is uploaded for UUID creation.