Utilities
Generate UUIDs, one or a thousand
Generate cryptographically random UUID v4 or time-ordered v7 identifiers, one at a time or in bulk.
For the best results: v4 is the everyday random ID. Choose v7 when IDs will be database keys. They sort by creation time, which keeps indexes fast. Bulk mode outputs one per line.
Runs entirely in your browser, what you paste is never uploaded, logged, or stored.
What is UUID Generator?
UUID Generator is a free online utility that generates cryptographically random UUID v4 or time-ordered v7 identifiers, singly or in bulk. The conversion runs as plain JavaScript in this tab, so whatever you paste, including anything sensitive, never leaves your device. There is no server call involved at all, no account to make, and no cap on how often you use it.
- ✦Runs entirely in your browser. Nothing you enter is ever uploaded
- ✦No account, no sign-up, and no data leaves your device
- ✦Works offline once the page has loaded
See it in action
A developer needs fresh unique IDs for seed data.
What you type
Click Generate
What you get
A valid v4 UUID such as 65a1892c-5de0-42ff-b9f1-8dc5b0556218, with the version and variant bits verified correct in testing, and a different value on every click.
Tip: These come from the browser's cryptographic random source, so they are safe for real identifiers, not just mock data. v7 is also available when you want IDs that sort by creation time.
Use cases
What people use it for
Seed a test database with a batch of fresh v4 identifiers as realistic primary keys.
Grab a single unique ID for naming a config entry, webhook or feature flag.
Generate time-ordered v7 UUIDs so newly inserted rows keep tidy database index locality.
Who uses UUID Generator?
Backend developers
mint identifiers for records, requests and idempotency keys without shipping a library for a one-off need
QA engineers
fill fixtures and test payloads with valid, unique IDs that will never collide with production data
Database administrators
compare v4 against v7 keys when planning primary key strategy for insert-heavy tables
How it works
- 1Vary step 1 by tool shape using the existing FORM_TOOL_IDS set in app/(public)/[category]/[tool]/page.tsx. Form tools get "Set the options for what you need." and text tools get "Paste your text into the box." Where a tool's config makes it easy, name its own inputs instead. Steps 2 and 3 stay shared as they are.
- 2Your browser computes the result instantly. Nothing is uploaded anywhere.
- 3Copy the output; the tool keeps working even offline.
Tips for the best results
- Prefer v7 for primary keys in tables with heavy insert traffic, the index stays compact.
- Store UUIDs in a native uuid column type where your database offers one; text columns waste space and compare slower.
- Lowercase is the canonical presentation, normalize before comparing values from different systems.
- Never truncate a UUID to make it prettier; the uniqueness guarantee applies only to the full 128 bits.
- Use bulk mode to pre-generate fixture IDs so test data stays stable between runs.
FAQ
Frequently asked questions
What is the difference between UUID v4 and v7?
Version 4 is 122 bits of pure randomness, no structure, no ordering, maximum unpredictability. Version 7 leads with a millisecond timestamp and fills the rest with random bits, so identifiers sort roughly by creation time. That single change matters enormously for databases: v7 keys insert at the end of an index instead of at random positions throughout it.
Could two generated UUIDs ever be the same?
In theory yes; in practice never worry about it. A v4 UUID carries 122 random bits, which means the space of possible values is so vast that you could generate billions per second for centuries without a realistic chance of a repeat. This is the entire point of UUIDs, machines can mint identifiers independently without ever coordinating with each other.
Where does the randomness actually come from?
From your browser's built-in cryptographic generator, the same source used for encryption keys and secure tokens, not the weak pseudo-random routine that games and animations rely on. Every identifier is minted on your device the moment you click, which also means none of them are transmitted, stored or known to anyone but you.
Is there any record of the UUIDs I generate?
None anywhere. Generation happens locally and the values exist only on your screen until you copy them. There is no server-side log to leak and no history to clear. You can safely mint identifiers for production systems, license keys or internal tooling without them ever having existed outside your machine.
What does the format of a UUID mean?
A UUID is 128 bits shown as 32 hexadecimal characters in five hyphenated groups, 8-4-4-4-12. The first character of the third group reveals the version, so a 4 there means v4 and a 7 means v7, and a handful of other bits encode the variant. The rest is payload: random bits, or timestamp plus random bits for v7.
How do I generate a UUID without installing anything?
Any modern browser can mint one natively, and this page wraps that capability with bulk output and a choice of version. Open it, pick v4 or v7, click generate and copy, no command line, no package manager, no sign-up. It even keeps working offline once the page has loaded.
Is a GUID the same as a UUID?
Functionally yes. GUID is Microsoft's historical name for the same 128-bit identifier, and the terms are interchangeable in modern use, a GUID field in SQL Server happily stores what everyone else calls a UUID. Formatting conventions occasionally differ, such as braces around the value in older Windows tooling, but the underlying identifier is identical.
Can a UUID be traced back to my computer?
Not with the versions generated here. The old v1 scheme embedded your network card's hardware address, which genuinely could identify a machine. Version 4 contains nothing but random bits, and v7 adds only a timestamp, neither carries any information about the device that created it.
Are there any usage limits?
None. Everything is generated locally in your browser, so there is no server cost, no metering, and no daily cap, use it as many times as you like, completely free.
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