How-to · Developer
How to generate a UUID in Chrome (UUID generator + ULID)
The short answer
Open DevKit's IDs tab and a fresh UUID v4 is already waiting — copy it, regenerate, or raise the count to mint a batch. Need sortable, database-friendly ids instead? Switch to ULID. Everything is generated locally with the browser's crypto RNG; nothing is sent anywhere.
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Click the DevKit icon in Chrome and open the IDs tab — a fresh UUID v4 is generated immediately.
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Copy the value, or hit regenerate for a new one.
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Switch to ULID when you need timestamp-prefixed identifiers that sort in creation order.
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Raise the count to mint a batch and copy them all at once.
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Everything is generated locally with the browser's crypto RNG — nothing is transmitted.
Needing "just one UUID" is the classic reason developers keep an online generator bookmarked. In Chrome you don't need the website: DevKit mints UUIDs and ULIDs directly in the extension popup, using the browser's cryptographic random number generator, with no page load and no network request.
Open the IDs tab
Click the DevKit icon and switch to the IDs tool. It generates a value the moment it opens, so the common case — one fresh UUID — is already on screen. Copy it and get back to work; hit regenerate if you want another.
Choose UUID v4 or ULID
UUID v4 is 122 bits of randomness (via crypto.randomUUID) in the format every database, SDK and spec expects; collisions are a theoretical curiosity, not a planning concern. ULID is the alternative worth knowing: a 48-bit millisecond timestamp followed by 80 random bits, rendered as 26 Crockford base32 characters. Because the timestamp leads, ULIDs sort lexicographically in creation order — friendlier as database primary keys and easier to eyeball in logs than v4 UUIDs, whose random spread scatters inserts across an index.
Generate a batch
Raise the count to mint several at once — for seeding fixtures, filling a spreadsheet or stubbing API data — and copy them as a block. ULIDs minted within the same millisecond still come out in creation order: DevKit implements the spec's monotonic path, incrementing the random component instead of gambling on it.
Why generate locally?
A UUID from a website is probably random enough — the honest argument for local generation isn't paranoia about entropy. It's that a popup is faster than a page load, that Chrome's own CSPRNG is doing the work rather than code you can't inspect, and that no server, ad script or analytics pixel ever observes the value. That last point starts to matter the moment an id graduates into a webhook token, an API key suffix or a support-visible reference.
Same popup, five more tools
The IDs tab lives next to a JWT decoder, Base64 and URL converters, a Unix timestamp converter and a regex tester. All six run offline; the extension's only permission is storage, used to remember which tool you had open. It's free, with no account and no tracking.