UUID Generator
Generate one or multiple UUIDs (v4) instantly. RFC 4122 compliant, cryptographically random. Free browser-based tool.
How UUID Generator Works
Generates UUID v4 using the browser's crypto.randomUUID() API. UUID v4 is 128 bits of random data formatted as 8-4-4-4-12 hexadecimal groups (xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx). Statistically impossible to collide (1 in 2^122 chance). No server calls — generation is instant and runs entirely in your browser.
Use Cases
Generate uuid generator
Create random uuid generator instantly with customizable options for your crypto tools needs.
Bulk Generation
Generate multiple uuid generator at once for testing, batch processing, or bulk operations.
Copy & Use
Copy generated results with one click and use them directly in your applications or workflows.
Customize Options
Fine-tune uuid generator generation with various settings and filters for specific requirements.
Frequently Asked Questions
What is a UUID?
A Universally Unique Identifier (UUID) is a 128-bit identifier formatted as 32 hex digits in five groups. UUID v4 is generated from random numbers. The probability of collision across all UUIDs ever generated is statistically negligible.
UUID vs ULID vs CUID — which should I use?
UUID v4: widely supported, truly random, no sortability. ULID: sortable by generation time (useful for database keys). CUID2: designed for high-collision environments. For most use cases, UUID v4 is the safe default.
Can I use UUIDs as database primary keys?
Yes, with caveats. UUIDs are larger than integer IDs (16 bytes vs 4–8 bytes) and random UUIDs cause index fragmentation in B-tree indexes. For performance, use ULIDs or UUID v7 (time-ordered) instead.
Is my data stored?
No. Generation runs in your browser only.
Can I use this on mobile?
Yes.
About This Tool
Built by the Calcyo team and last updated June 2026. All calculations follow industry-standard methodology. No data leaves your browser — calculations run entirely client-side using JavaScript. If you spot an error in the formula or benchmark data, email us at support@calcyo.xyz.