UUID · Validation · Version · Timestamp
Validate a UUID Online
Updated: May 2026
Check that a UUID is well-formed, identify its version, verify the RFC 4122 variant and extract the timestamp from a UUID v7 — all in one click, directly in the browser with the Flowfiles Validate tool.
Free · No upload · Validated in the browser
Valid UUID format
An RFC 4122 compliant UUID follows this pattern:
xxxxxxxx-xxxx-Mxxx-Nxxx-xxxxxxxxxxxx- 32 hex characters in 5 groups separated by dashes.
- M (position 13): hex digit representing the version (1, 2, 3, 4, 5, 6, 7 or 8).
- N (position 17):
8,9,aorbfor RFC 4122 variant.
The tool also accepts: uppercase, no-dash format (32 chars), curly braces {...}, URN prefix urn:uuid:.
Detecting UUID version
The 13th character (first character of the 3rd group) indicates the version:
1: UUID v1 — MAC timestamp (legacy, avoid for new apps).4: UUID v4 — fully random.7: UUID v7 — Unix ms timestamp + random.
Example: f47ac10b-58cc-4372-a567-0e02b2c3d479 → version 4.
UUID v7 timestamp extraction
uuid = "0192f6a4-1234-7abc-9def-0123456789ab"
hex_ts = "0192f6a41234" // first 12 chars (no dashes)
ms = parseInt("0192f6a41234", 16) // 1747820716596
date = new Date(ms).toISOString() // "2025-05-21T09:25:16.596Z"Frequently asked questions
Can you validate a UUID without dashes?
Yes. The tool accepts UUIDs without dashes (32 hex chars), with braces, and with URN prefix. It normalizes them automatically before validation.
Is an uppercase UUID valid?
Yes. RFC 4122 specifies that case is irrelevant. F47AC10B-58CC-4372-A567-0E02B2C3D479 is identical to its lowercase version.
How to validate a UUID in JavaScript?
Use the regex /^[0-9a-f]{8}-[0-9a-f]{4}-[1-8][0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/i. It validates format, version and RFC 4122 variant.