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The most recent data you entered in this tool, stored only in this browser.
Save what you type here, in this browser? Your work would go into this browser's local storage, so a refresh or a trip to another tool does not wipe it. You also get a short list of previous entries under the form, each one restorable with a click. Nothing is ever uploaded, and there is no account.
Being straight about the trade-off: anything kept there can be read by anyone who can use this browser profile, and by any script that later runs on this site. A tool page can hold a private key, a password or a signed token. Saving is convenient; it is not private.
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About this tool
Generate version 4 UUIDs, one at a time or in bulk, using the browser’s cryptographic random number generator. They are suitable for database keys, request IDs and anything else that has to be unique without coordinating with a central authority.Questions
- Can two generated UUIDs collide?
- A v4 UUID carries 122 random bits. You would need to generate around 2.7×10^18 of them before a collision became likely, which is far beyond any realistic workload.
- Are these UUIDs predictable?
- No. They come from crypto.getRandomValues rather than Math.random, so earlier values tell you nothing about later ones.