Validators

UUID Validator

Check if a UUID is in standard v4 UUID format.

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How to use

  1. 1Paste the UUID.
  2. 2Click Process.
  3. 3See if it is valid.

About

Validates the standard UUID v4 format, useful for checking identifiers in databases and APIs.

How to validate a UUID correctly

The UUID validator checks whether a string follows the 8-4-4-4-12 format of a universally unique identifier, and identifies the version and variant. It is useful for reviewing identifiers in databases, APIs, and logs.

A UUID is made of 32 hexadecimal characters organized in five groups: 8-4-4-4-12, like 550e8400-e29b-41d4-a716-446655440000. The tool checks the format, the characters, and the positioning of the hyphens.

The version indicates how the UUID was generated. Version 4 is the most common, generated by randomness, and has specific reserved bits (the "4" at position 13 and one of 8, 9, a, or b at position 17).

It is important to distinguish valid format from uniqueness. A well-formed UUID is practically guaranteed unique by the size of the combination space, but the tool validates only the structure, not uniqueness within a dataset.

Examples

  • 550e8400-e29b-41d4-a716-446655440000 → valid (version 4).
  • 550e8400-e29b-41d4-a716-4466554400 → invalid (final group with 11 digits instead of 12).

Limitations

  • Validation checks format and version, but does not guarantee the UUID is unique within your dataset.
  • There are variants and alternative formats (such as UUIDs without hyphens) that may not be accepted depending on the implementation.

How to use the UUID validator

  1. 1Paste the UUID into the main field.
  2. 2Click Process.
  3. 3See whether it is valid and the detected version.

Frequently asked questions

What does the UUID version mean?

The version indicates the generation method: v1 uses timestamp and MAC, v3/v5 use name hashing, and v4 uses randomness. v4 is the most used in modern applications.

Can two UUIDs be equal?

The probability is negligible for version 4 (about 1 in 2^122). In practice, collisions do not happen in normal use.

Do I need the hyphens?

The canonical format uses hyphens. Some systems accept without hyphens, but standard validation expects the 8-4-4-4-12 format.

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