Have you ever pasted an identifier into a database and watched the insert fail over one wrong character? A UUID Validator checks the shape of each identifier before it causes that kind of error. This tool reads a list of UUIDs and marks every line as valid or invalid.
The UUID Validator here checks syntax only. It confirms the 8-4-4-4-12 hex pattern, reads the version digit, and counts how many lines pass. It is built for developers, testers, and data teams cleaning identifier lists.
Table of Contents
- What the Validator Checks
- How to Use It, Step by Step
- The UUID Pattern It Matches
- Worked Example
- How to Read the Results
- Syntax Versus Real Uniqueness
- Limitations and Assumptions
- FAQs About the UUID Validator
What the Validator Checks
The tool reads one UUID per line, pasted or typed. It then tags each line and updates four counters as you work.
- Trims spaces and strips wrapping braces and quotes from both ends.
- Matches the standard hyphenated 8-4-4-4-12 hex pattern.
- Reads the version digit, from 1 through 5, on a matching line.
- Also accepts a compact 32 hex form with no hyphens.
- Labels each line with its version, or as invalid syntax.
- Total Checked, Valid Count, Invalid Count, and Pass Rate update live.
- Copy Valid Only and Copy Invalid Only export each group.
How to Use It, Step by Step
- Paste your identifiers into the UUID / GUID List (One per line) box.
- Keep one UUID on each line.
- Watch the list update as you type, since there is no submit button.
- Read the colored rows: green means valid, red means invalid.
- Press Load Sample to see six mixed examples.
- Press Clear to empty the box and reset the counters.
- Press Copy Valid Only or Copy Invalid Only to export a group.
The UUID Pattern It Matches
A UUID is a 128-bit value written as 32 hex digits in five blocks. The tool checks that shape with a strict pattern.
8 hex-4 hex-version + 3 hex-variant + 3 hex-12 hex=Valid UUID
- Each block uses hex digits 0 to 9 and a to f, in either case.
- The version digit must be 1, 2, 3, 4, or 5.
- The variant digit must be 8, 9, a, or b.
- The compact form is any 32 hex digits with no hyphens.
Worked Example
Press Load Sample and the tool loads six lines. Here is how it tags each one.
| Line | Result | Why |
|---|
| f47ac10b-58cc-4372-a567-0e02b2c3d479 | Valid v4 | Matches the pattern, version digit 4 |
| {a0eebc99-9c0b-4ef8-...} | Valid v4 | Braces stripped first, version digit 4 |
| 12345678-1234-1234-1234-123456789abc | Invalid | Variant digit is 1, not 8 to b |
| not-a-valid-uuid-string | Invalid | Wrong length and characters |
| f47ac10b58cc4372a5670e02b2c3d479 | Valid, Compact | 32 hex digits, no hyphens, no version check |
| 00000000-0000-0000-0000-000000000000 | Invalid | Version digit is 0, outside 1 to 5 |
So three lines pass and three fail. Total Checked reads 6, Valid Count reads 3, and the Pass Rate reads 50 percent.
How to Read the Results
Total Checked is the number of non-empty lines. Valid Count in green is the lines that match either pattern.
Invalid Count in red is the lines that match neither. Pass Rate is valid divided by total, rounded to a whole percent.
Each row carries a small tag. A valid hyphenated row shows its version digit. A compact row reads Compact, and a failing row reads Invalid Syntax.
Syntax Versus Real Uniqueness
A pass here means the text has the right shape. It does not mean the UUID was ever issued or is truly unique. Two identical valid lines both pass, since the tool does not detect duplicates.
The compact 32-hex form is tagged Compact, with no version check. The tool reads no version digit from that form, so treat such a pass with care.
Need fresh identifiers instead? The UUID generator builds one at a time, and the UUID bulk generator makes long lists. The GUID generator follows the same layout for Microsoft style IDs. For shorter, URL-friendly IDs, see the Nano ID generator. More utilities live in the developer tools hub.
Limitations and Assumptions
- Validation is syntax only, with no check of uniqueness or existence.
- Only versions 1 through 5 pass in the hyphenated form.
- The all-zero nil UUID is marked invalid, though some systems treat it as special.
- The compact form skips the version and variant checks.
- Results are not saved and live only in your browser session.
- Special characters in a line are escaped and shown as plain text.
FAQs About the UUID Validator
What Does the UUID Validator Check?
It checks the syntax of each line against the standard UUID pattern. It confirms the 8-4-4-4-12 hex layout and reads the version digit. It also accepts a compact 32 hex form.
Does a Valid Result Mean the UUID Is Unique?
No. A valid result means the text has the right shape. The tool does not test whether the value is unique or whether any system issued it.
Why Was My Version 7 UUID Marked Invalid?
The hyphenated pattern allows only version digits 1 through 5. Newer versions, such as 6, 7, and 8, fall outside that range. They are tagged as invalid syntax here.
Can I Check Many UUIDs at Once?
Yes. Put one UUID on each line in the input box. The tool checks every line and updates the counters as you type.
Is Uppercase or Lowercase Accepted?
Both work. The pattern allows hex digits a to f in either case. So f47ac10b and F47AC10B are treated the same way.
Does the Tool Store My UUIDs?
No. The check runs in your browser, and nothing is sent to a server. The counters and list reset when you clear the box or reload.
This calculator gives general estimates only and is not professional advice. Reviewed for general accuracy by Prof. Dr. Khalil Mudassar, PhD.