UUID v4 for random identifiers
v4 is the usual pick for database keys, request IDs, and anything that should not leak a clock. Generate one or a batch when you are seeding fixtures or filling a spreadsheet without standing up a script.
Generate UUID v1, v4, and NIL identifiers in bulk, with uppercase and hyphen options, all in your browser — free online UUID tool, no signup or upload.
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v4 is the usual pick for database keys, request IDs, and anything that should not leak a clock. Generate one or a batch when you are seeding fixtures or filling a spreadsheet without standing up a script.
v1 includes a timestamp-style layout some older systems still expect. NIL is the all-zero UUID for placeholders and “empty” values in APIs. Switch versions without leaving the page.
Produce a list, then match the format the consumer wants: with or without hyphens, upper or lower hex. Copy the whole batch into a migration or a test harness in one go.
Identifiers are created in your browser. There is no upload and no account. You are not sending a count of IDs to a remote generator.
Use v4 unless you have a reason for time-based v1 or the NIL placeholder. The version is shown in the stats.
Choose how many UUIDs to generate and whether they use capitals and hyphen separators.
Run generate to fill the list. Each refresh produces new v4/v1 values; NIL stays the zero UUID.
Copy one line or the whole list into your code or spreadsheet. Nothing is stored on a server.
Straight answers on privacy, limits, and how the workspace behaves.
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