UUID/ULID & Password Generator
A tool for bulk-generating up to 1,000 UUIDs (v4 and v7) or ULIDs, and for creating secure passwords with a custom length and character set. It uses the cryptographically secure crypto.getRandomValues, and everything is generated in your browser.
The most common UUID, made of 122 random bits.
Generate between 1 and 1000 at once.
How to use
- Choose what to generate from the "UUID", "ULID", and "Password" tabs.
- For UUIDs, pick the version (v4/v7); for passwords, set the length and character types. You can also change how many to generate and toggle uppercase or hyphens.
- Values are regenerated automatically whenever you change a setting. Click "Regenerate" to get new values with the same settings.
- Use "Copy to clipboard" or "Save as text" to take all the results at once.
About this tool
A UUID (Universally Unique Identifier) is a 128-bit ID used to uniquely identify things like database records and API resources. v4 is made almost entirely of random bits, while v7 starts with the creation time so values sort chronologically. A ULID likewise begins with a timestamp and is a 26-character ID written in URL-friendly uppercase Crockford Base32.
v7 and ULIDs have good index locality, which makes them efficient as database primary keys. This tool uses a counter to guarantee creation order even when many values are generated within the same millisecond; for v7 it follows RFC 9562 and uses the 12 bits after the timestamp as the counter.
Passwords include at least one character from each selected type, and characters are chosen with rejection sampling to avoid modulo bias. The displayed strength is a guide based on theoretical entropy (bits) derived from the length and character types. UUIDs, ULIDs, and passwords are all generated with crypto.getRandomValues, not Math.random.
Frequently asked questions
Should I use UUID v4 or v7?
Use v4 when you need an unpredictable random ID, and v7 when you want IDs that sort in creation order, such as database primary keys. Note that the creation time can be read from a v7 ID.
Can generated UUIDs collide?
v4 has 122 random bits, so the chance of a collision is negligible in practice. v7 and ULIDs also include plenty of randomness in addition to the timestamp, and values within the same millisecond are distinguished by a counter.
How strong should my password be?
For typical web services, aim for at least 16 characters with upper- and lowercase letters, digits, and symbols (about 100 bits). We recommend using a password manager and a different password for each service.
Are generated passwords stored or sent anywhere?
No. Generation happens only in your browser, and the values disappear when you close the page.