What is a UUID generator?
A UUID generator creates unique identifiers in UUID format. This tool generates UUID v4 and UUID v7 directly in your browser.
UUID Generator
With the UUID Generator you can create UUID v4 and UUID v7 for free, without sign-in and locally in your browser – individually or in bulk.
UUIDs are generated directly in your browser. No UUIDs are sent to our server or external services, and none are stored.
Generate UUIDs
UUID v4 uses random bits and suits general unique identifiers.
Between 1 and 1,000 UUIDs per run.
Result
Validate UUID
The validator checks structure, version and variant. It cannot determine which system actually created a UUID.
Understanding and using UUIDs
What is a UUID?
A UUID (Universally Unique Identifier) is a standardised fixed-length identifier used to label objects, records or resources uniquely without central assignment.
What are UUIDs used for?
UUIDs appear in databases, APIs, logs, distributed systems, filenames and test data. They help avoid collisions and reference data across system boundaries.
How does UUID v4 work?
UUID v4 is built mostly from cryptographically secure random values. Version and variant bits are fixed. It suits cases where sortable time information is not needed.
What is UUID v7?
UUID v7 contains a 48-bit timestamp in milliseconds plus random parts. UUIDs can be sorted lexicographically by creation time – useful in databases and logs.
UUID v4 or UUID v7 – which should I use?
For general unique IDs without sorting needs, UUID v4 is common. When you need chronological sortability, UUID v7 is often the better choice.
Are UUIDs truly unique?
Collision probability is extremely low with correct generation, but not mathematically zero. In practice duplicates are negligible for v4 and v7.
Are UUIDs secret or security-relevant?
No. UUIDs are identifiers, not secrets. They must not be used as passwords, tokens or sole protection for sensitive resources.
Can a UUID be used as a password or access token?
That is not recommended. Although UUIDs can look long and random, they are not designed for authentication or secrecy. Use password managers and dedicated token schemes instead.
What is the difference between UUID and GUID?
GUID (Globally Unique Identifier) is the term from the Microsoft world. Technically it is usually the same 128-bit format as UUID.
Why are UUIDs generated locally in the browser?
Local generation prevents identifiers from being transmitted or stored over the network. That matches this tool’s privacy goal.
Related tools
Frequently asked questions about the UUID Generator
What is the difference between UUID v4 and UUID v7?
UUID v4 is random. UUID v7 also embeds a timestamp and is therefore lexicographically sortable by creation time.
Which UUID version should I use?
For general IDs: UUID v4. For time-sortable IDs in databases or logs: UUID v7.
How likely are duplicate UUIDs?
With correct generation, collision probability is extremely low and can usually be ignored in practice.
Can I generate multiple UUIDs at once?
Yes. You can generate up to 1,000 UUIDs in one run.
Are my UUIDs stored?
No. There is no storage on the server, in cookies or in local storage.
Can I download the UUIDs?
Yes. Depending on format as TXT, JSON, CSV or SQL – generated entirely locally.
What is the difference between UUID and GUID?
GUID is essentially another name for the same identifier format, especially in Microsoft environments.
Can I use a UUID as a password?
That is not recommended. UUIDs are identifiers, not secure secrets or authentication tokens.
Can you read the creation time from a UUID v7?
Yes. The first 48 bits contain the Unix timestamp in milliseconds. The validator and result view show it.
Does letter case matter for UUIDs?
No. UUIDs are equivalent regardless of case. This tool normalises to lowercase by default.
Is a UUID without hyphens still valid?
Yes, as long as the 32 hex characters are correct. The validator also accepts representations without hyphens.