Which UUID version should I use?

v4 for general identifiers, v7 when you want database-friendly time ordering, and v5 when the same input must always map to the same UUID. v1/v6 mainly serve compatibility with existing systems.

What makes v7 better for database keys?

Its first 48 bits are a Unix timestamp, so freshly generated keys sort together — index pages stay hot and inserts stay fast, unlike fully random v4 keys.

Are v1 UUIDs a privacy risk here?

No — the spec-sanctioned random node (multicast bit set) is used instead of your real MAC address.

How random are the random strings?

Characters are drawn with crypto.getRandomValues using rejection sampling, so every character in your pool is equally likely; the entropy meter shows the resulting strength in bits.

UUID Generator (v1–v7) & Random String

Generate UUIDs of every version in bulk: random v4, timestamp-sortable v7 and v6, classic v1, and deterministic name-based v3/v5 (with standard DNS/URL/OID namespaces). A random-string mode produces crypto-grade tokens with your choice of length and characters — all in your browser.

How to use UUID Generator (v1–v7) & Random String

Pick a UUID version (or Random string) — results regenerate instantly as you change options.
Set the count for bulk generation; v3/v5 take a namespace and one name per line instead.
Copy all results with one click — toggles for UPPERCASE and hyphen-free formats included.

Frequently asked questions

Which UUID version should I use?: v4 for general identifiers, v7 when you want database-friendly time ordering, and v5 when the same input must always map to the same UUID. v1/v6 mainly serve compatibility with existing systems.
What makes v7 better for database keys?: Its first 48 bits are a Unix timestamp, so freshly generated keys sort together — index pages stay hot and inserts stay fast, unlike fully random v4 keys.
Are v1 UUIDs a privacy risk here?: No — the spec-sanctioned random node (multicast bit set) is used instead of your real MAC address.
How random are the random strings?: Characters are drawn with crypto.getRandomValues using rejection sampling, so every character in your pool is equally likely; the entropy meter shows the resulting strength in bits.

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