Bulk UUID Generator
Generate hundreds or thousands of UUIDs in one batch and download them as a text file — for seed data, migrations and load tests. Everything runs locally in your browser, with no per-ID limits sold back to you.
Why bulk generation is its own tool
Clicking "generate" five hundred times is not a workflow. Seed scripts, data migrations, anonymised test datasets and load-test harnesses all need identifiers by the hundreds, formatted identically and delivered as a file. This page points the UUID generator at exactly that job: set a count, get a clean list, download it as text. No accounts, no API keys, no rate limits — the computation happens on your machine, so the batch size is your hardware's business, not a pricing tier's.
Uniqueness at scale
Scepticism is healthy here: surely a million random IDs must contain a duplicate? Run the birthday maths and the answer is reassuring. With 2¹²² possible values, a batch of one million has a collision probability of roughly 10⁻²⁵ — for comparison, you are far more likely to be hit by a meteorite while reading this sentence. Bulk v4 generation is exactly how large systems pre-mint IDs for offline devices and edge nodes. If you only need a handful, the random UUID generator is the lighter page; for the format details see the UUID v4 generator.
Working with the output
One UUID per line is deliberately boring: it pastes into a SQL INSERT, a jq or awk pipeline, a spreadsheet column or a fixture file without cleanup. Need uppercase or braces for a Windows-flavoured codebase? That is a two-second find-and-replace in any editor, and the GUID page explains the naming difference.
Private by design
The full batch exists only in your browser tab. Close it and the list is gone — download first if you need it later.
Frequently asked questions
How many UUIDs can I generate in one batch?
The generator builds the whole list in your browser, so the practical limit is your device's memory and patience rather than an artificial cap. Batches of several thousand complete in seconds on a typical laptop.
What format does the downloaded file use?
Plain text, one UUID per line, in canonical lowercase hyphenated form (8-4-4-4-12). That drops directly into SQL VALUES lists, CSV seed files and test fixtures.
Are bulk-generated UUIDs still unique?
Yes. Each value is an independent draw from cryptographic randomness with 122 random bits, so a batch of a million still has a negligible collision probability — around one in 10²⁵.
Can I use these for database seeding?
That is the main use case: primary keys for seed rows, synthetic users for load tests, and placeholder IDs for import pipelines. Because they are standard v4 UUIDs, any database or ORM accepts them as-is.
Is my batch uploaded or logged?
No. The batch is generated and downloaded entirely on your device. Nothing is sent to or kept on a server.
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