UUID generator
Create secure random v4 or timestamp-based v7 UUIDs in batches.
Whole number from 1 to 1,000.
Generated UUIDs are not saved. Only your options are remembered and included in the page URL.
V7 includes a timestamp. Order within one millisecond is not guaranteed.
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Generate UUIDs for database records, test fixtures, request identifiers, or configuration files. Choose random version 4 or version 7, which starts with a Unix timestamp in milliseconds. Create one identifier or a batch of up to 1,000, then copy one ID per line. Uppercase and hyphen options change the display without generating new values. Generation runs in your browser using its cryptographic random source. The results stay on the page and are not saved or added to the page address.
How to use
- Choose UUID v4 or UUID v7.
- Enter a whole number from 1 to 1,000.
- Select Generate, or press Ctrl/⌘ + Enter inside the tool.
- Adjust uppercase or hyphens, then select Copy all.
- Use Clear to remove the current results.
What it handles
- V4 uses crypto.randomUUID; v7 combines a timestamp with secure random bits.
- Creates up to 1,000 UUIDs, with one identifier on each line.
- Changes letter case and hyphens without replacing the generated IDs.
- Stops with an error if secure generation is unavailable.
- Remembers options only; generated values are never stored by the tool.
FAQ
What is the difference between UUID v4 and v7?
V4 has 122 random bits after its fixed version and variant bits. V7 starts with a 48-bit Unix timestamp in milliseconds and uses 74 random bits here. Its timestamp helps group values by generation time. Choose the version your application expects; changing the display format does not change a UUID’s version.
Are v7 UUIDs always generated in increasing order?
This implementation uses fresh randomness after the timestamp, without a counter. Values from the same millisecond are not guaranteed to increase, and a clock that moves backward can also affect ordering. A v7 UUID exposes its generation timestamp. Use it when that property fits your application rather than treating it as a secret token.
Can I generate UUIDs without a secure connection?
This tool requires a secure browser context, normally HTTPS or localhost, and the corresponding Web Crypto methods. If they are missing or fail, generation stops and no partial batch is shown. There is no weaker random fallback. UUIDs are identifiers; generating them does not create passwords, access controls, or a guarantee against every possible collision.
Can I recover a batch after reloading the page?
No. The tool remembers only your options and includes non-default choices in the page query. Generated UUIDs are neither saved locally nor placed in the address. Copy anything you need before reloading. Each Generate action replaces the previous batch, while formatting switches retain the same values. Clear removes the visible results.
Updated