What are the key differences between UUID versions 1, 4, and 7?

Version 1 uses host MAC address and timestamp. Version 4 uses 122 pseudo-random bits. Version 7 is a modern RFC 9562 standard using Unix epoch millisecond timestamps, offering time-sortability and excellent database indexing performance.

What constitutes a valid UUID string format?

A standard UUID is a 36-character string comprising 32 hexadecimal digits displayed in five groups separated by hyphens (8-4-4-4-12), such as 123e4567-e89b-12d3-a456-426614174000.

How does the validator detect UUID version numbers?

The version number is stored in the 13th hexadecimal character (the high 4 bits of the time_hi_and_version field). For instance, a 4 in that position (xxxx-xxxx-4xxx-xxxx-xxxxxxxxxxxx) denotes UUID v4.

What is a Nil UUID and is it considered valid?

A Nil UUID consists of 128 zero bits (00000000-0000-0000-0000-000000000000). It is a valid special-case UUID defined in RFC 4122 used to indicate an uninitialized or empty identifier.

Can this tool extract embedded timestamps from UUID v1 or v7?

Yes, because UUID v1 and UUID v7 encode timestamps directly into their bit structures, our validator decodes these bytes to display the exact UTC timestamp when the UUID was generated.

How many UUIDs can I validate in a single batch?

Since validation executes entirely in client-side JavaScript, you can validate tens of thousands of UUIDs instantly. Maximum batch size is limited only by your browser's available system memory.

Does this tool support UUIDs without hyphens (32-character hex)?

Yes, the validator recognizes 32-character unhyphenated hexadecimal strings, identifies their embedded version and variant, and can format them back into standard hypenated 8-4-4-4-12 representations.

Is my database identifier list uploaded or stored on any server?

No. The parsing, regex format matching, and bitwise version extraction are processed 100% locally in your browser memory. No telemetry or dataset contents are sent off your machine.

UUID Validator

Validate UUIDs in bulk: format check, version detection (v1/v3/v4/v5/v7), variant bits, and nil-UUID recognition. Free, in-browser.

100% Private — Runs entirely in browserInstant calculation & resultFree, no sign-up

UUIDs (one per line, up to 100)

Why use a bulk UUID validator for database & API auditing?

Universally Unique Identifiers (UUIDs) are 128-bit numbers used extensively across databases, distributed microservices, event streams, and REST APIs to uniquely identify records without central coordination. During database migrations, log analysis, or API payload verification, developers frequently encounter corrupt, malformed, or misformatted UUIDs that cause silent database join failures or API validation exceptions.

A dedicated bulk UUID validator analyzes thousands of candidate strings simultaneously. In addition to confirming string length and hyphen placement, it decodes embedded RFC 4122 and RFC 9562 metadata—identifying the exact UUID version, variant bits, and creation timestamps—enabling software engineers to quickly audit system primary keys.

Bulk Format Validation: Process thousands of UUID strings at once, quickly isolating invalid character lengths, non-hexadecimal characters, or missing hyphens.
Automated Version Detection: Instantly categorize UUID versions including time-based (v1, v7), MD5 namespace (v3), random (v4), SHA-1 namespace (v5), and Nil UUIDs.
Variant Bit Decoding: Inspect RFC 4122 variant bits (Leach-Salz variant, legacy Microsoft GUID compatibility, or reserved variants) encoded within byte fields.
Batch Export & Filtering: Filter out invalid identifiers and export clean lists of valid UUIDs to clipboard with a single click for fast dataset remediation.

RFC 4122 and RFC 9562 UUID architecture

Standard UUIDs consist of 128 bits represented as 32 hexadecimal characters broken into 5 hyphen-separated groups: 8-4-4-4-12 (for example, f47ac10b-58cc-4372-a567-0e02b2c3d479). The 13th hex character (the highest 4 bits of the time_hi_and_version field) indicates the version number (e.g., 4 for random UUID v4, 7 for Unix epoch time-ordered UUID v7).

The 17th hex character (the highest 2 to 3 bits of the clock_seq_hi_and_reserved field) specifies the variant. Variant 1 (binary 10x) complies with RFC 4122 / RFC 9562. For time-based variants like UUID v1 and UUID v7, the timestamp bits can be reconstructed into absolute UTC date-time objects, allowing developers to audit when an identifier was originally generated.

Client-side security for private database identifiers

All UUID strings, database records, and log entries analyzed by this tool are parsed purely in local web browser memory. No data is stored, logged, or uploaded to any remote web server.

Step-by-step guide to validating UUIDs in bulk

Paste Candidate Identifiers: Copy and paste your batch of UUID strings into the validator text area (separated by newlines, commas, or spaces).
Analyze Validation Metrics: Review instant diagnostic breakdowns showing format validity, extracted version numbers, variant types, and timestamp metadata.
Filter and Export Results: Separate malformed strings from valid identifiers and copy cleaned datasets directly back into your workflow.

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Frequently Asked Questions

What are the key differences between UUID versions 1, 4, and 7?
Version 1 uses host MAC address and timestamp. Version 4 uses 122 pseudo-random bits. Version 7 is a modern RFC 9562 standard using Unix epoch millisecond timestamps, offering time-sortability and excellent database indexing performance.
What constitutes a valid UUID string format?
A standard UUID is a 36-character string comprising 32 hexadecimal digits displayed in five groups separated by hyphens (8-4-4-4-12), such as 123e4567-e89b-12d3-a456-426614174000.
How does the validator detect UUID version numbers?
The version number is stored in the 13th hexadecimal character (the high 4 bits of the time_hi_and_version field). For instance, a 4 in that position (xxxx-xxxx-4xxx-xxxx-xxxxxxxxxxxx) denotes UUID v4.
What is a Nil UUID and is it considered valid?
A Nil UUID consists of 128 zero bits (00000000-0000-0000-0000-000000000000). It is a valid special-case UUID defined in RFC 4122 used to indicate an uninitialized or empty identifier.
Can this tool extract embedded timestamps from UUID v1 or v7?
Yes, because UUID v1 and UUID v7 encode timestamps directly into their bit structures, our validator decodes these bytes to display the exact UTC timestamp when the UUID was generated.
How many UUIDs can I validate in a single batch?
Since validation executes entirely in client-side JavaScript, you can validate tens of thousands of UUIDs instantly. Maximum batch size is limited only by your browser's available system memory.
Does this tool support UUIDs without hyphens (32-character hex)?
Yes, the validator recognizes 32-character unhyphenated hexadecimal strings, identifies their embedded version and variant, and can format them back into standard hypenated 8-4-4-4-12 representations.
Is my database identifier list uploaded or stored on any server?
No. The parsing, regex format matching, and bitwise version extraction are processed 100% locally in your browser memory. No telemetry or dataset contents are sent off your machine.