UUID generator online (v4, v7 and ULID)
Generate UUID v4, time-ordered UUID v7 and ULID, one or thousands at a time. Uppercase, no hyphens and a UUID validator.
Validate a UUID
How it works
Pick the identifier type and how many you need and get a list ready to copy or download. UUID v4 values are fully random; UUID v7 and ULID start with a timestamp, so they sort chronologically and work better as database primary keys.
They are generated with the browser cryptographic generator (crypto.getRandomValues). Below you can paste any UUID to check whether it is valid and which version it is.
Frequently asked questions
Can a UUID v4 repeat?
In practice, no. It has 122 random bits: you would need to generate billions per second for decades to have a meaningful chance of collision.
Should I use UUID v7 instead of v4?
For primary keys, yes: because they are time-ordered, database indexes fragment much less and inserts are faster.
Related tools
JSON validator and formatter online
Validate, beautify, minify and sort JSON online. Shows the exact error line and column. Free, and your data never leaves your browser.
Open toolBase64 encode and decode online
Encode and decode Base64 text with full UTF-8 support (accents, emojis), URL-safe variant, and file or image to Base64 conversion.
Open toolURL encode and decode online
Encode and decode URLs and query parameters (percent-encoding), and break a URL down into protocol, host, path and parameters.
Open toolMD5, SHA-1, SHA-256 and SHA-512 hash generator
Compute the MD5, SHA-1, SHA-256, SHA-384 and SHA-512 hash of text or a file, in hex or Base64. Ideal for verifying downloads.
Open toolJWT decoder online
Decode a JSON Web Token and read its header, payload, and issued-at and expiry dates in a readable format. The token never leaves your browser.
Open toolHTML entities encoder and decoder
Escape special characters to HTML entities (< > & ") or turn entities back into text. Optional encoding of non-ASCII characters.
Open toolNeed a custom tool for your business?
Tell us about your case and in 30 minutes we'll give you a clear diagnosis: what's going on, what to do first and what it might cost. No strings attached.