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UUID generator, GUID generator and UUID validator
Generate up to 100 UUIDs and validate existing UUID values.
UUID generator and validator
UUID generator and validator
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UUID generator and validator
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UUID generator and validator
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UUID generator and validator
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UUID generator and validator
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UUID generator and validator
UUID generator and validator
UUID generator and validator
Examples
UUID v4
550e8400-e29b-41d4-a716-446655440000
UUID v7
019e8eb6-b49c-7a57-aced-aff757cee34d
UUID Guides & articles
How UUIDs Create Identifiers Without Central Coordination
UUIDs let independent systems create identifiers with an extremely low collision risk, changing how records can be created, merged, and shared.
Read articleChoosing the Right UUID Version
Random, time-ordered, and name-based UUIDs provide different guarantees. Selecting a version should follow system requirements rather than habit.
Read articleUUID Mistakes in Databases and APIs
UUIDs remove central allocation, but careless storage, validation, indexing, and authorization can turn convenient identifiers into avoidable problems.
Read articleRelated tools
UUID generator, GUID generator and UUID validator is often used together with JSON formatter, JSON validator and JSON decoder online, MD5, SHA-256, SHA-512 and hash generator online, Regex tester, regular expression checker and replacer when payloads, tokens, URLs, logs, or markup move through the same workflow.
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Test expressions, flags, matches and replacement output live.
Open Regex tester, regular expression checker and replacerUUID generator and validator
Generate up to 100 UUIDs and validate existing UUID values. DevToolGrid Online offers a free UUID generator, GUID generator and UUID validator.
What is a UUID?
A UUID (Universally Unique Identifier), also called a GUID, is a 128-bit value written as 36 characters such as 550e8400-e29b-41d4-a716-446655440000. UUIDs let independent systems create identifiers — for database rows, files or events — without a central authority, with a vanishingly small chance of collision.
How to generate a UUID
- 1 Choose a version: v4 (random), v7 (time-ordered), v1, v3/v5 (name-based) or NIL.
- 2 Set how many to generate and pick format options like uppercase, braces or URN.
- 3 Click Generate, then copy the list or download it as a file.
- 4 Paste an existing UUID into the validator to check it and detect its version.
UUID notes and pitfalls
- Random is not sequentialv4 is fully random, which scatters database indexes. Use v7 when you need time-ordered, index-friendly ids.
- v1 can leak informationVersion 1 embeds a timestamp and node identifier. Prefer v4 or v7 if that metadata is sensitive.
- Case and formattingUUIDs are case-insensitive but usually lowercase. Braces and the urn:uuid: prefix are optional styles.
UUID v4 vs v7 (and GUID)
v4 is generated from random bits and is the most common choice for general ids. v7 places a millisecond timestamp at the front, so values sort by creation time and behave better as database keys. GUID is simply Microsoft’s name for the same 128-bit UUID standard.
FAQ
Is this tool free?
Yes. The UUID generator and validator are completely free with no limits.
Is my data sent to a server?
No. UUIDs are generated locally in your browser using the secure random generator; nothing is uploaded.
Can two UUIDs ever collide?
In practice no. The number of random v4 UUIDs is so large that a collision is astronomically unlikely.
Which version should I use?
Use v4 for general purposes and v7 for database keys that benefit from time ordering.