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🎲 UUID Generator

Generate UUIDs / GUIDs in bulk — runs in your browser

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What is a UUID?

A UUID (Universally Unique Identifier), also called a GUID in the Microsoft world, is a 128-bit value formatted as 32 hexadecimal digits separated by hyphens — for example, 550e8400-e29b-41d4-a716-446655440000. UUIDs are designed to be unique across space and time without coordination between systems, which makes them ideal for database keys, distributed system IDs, file names, session tokens, and any case where you need a unique value without consulting a central authority.

UUID versions explained

v4 (random) — 122 random bits make it cryptographically unpredictable. The most common choice in modern apps and the recommended default. v1 (timestamp) — based on the current time and a node identifier. Sortable by generation time but leaks the time and original machine. Useful when you want chronological ordering. NIL UUID — special all-zeros value (00000000-0000-0000-0000-000000000000), used as a placeholder or unknown marker.

When to use a UUID

Common use cases: primary keys in distributed databases where auto-increment is impossible, idempotency keys for API requests, correlation IDs in logs and traces, file or upload identifiers that must not collide, session tokens, secret reset tokens, anonymous device IDs, or any unique resource identifier exposed through an API.

Why use FileTools UUID Generator?

✅ Free — no signup, no spam
✅ 100% private — generated in your browser via Web Crypto API
✅ v4, v1, and NIL versions
✅ Bulk generation up to 10,000 at once
✅ Format options: hyphens, uppercase, braces, quotes
✅ Export as TXT, CSV, or JSON

Frequently Asked Questions

What is a UUID?

A 128-bit identifier formatted as 32 hex digits with hyphens. Unique without coordination, perfect for database keys and distributed systems.

What is the difference between v1 and v4?

v1 uses timestamp + node — sortable by time but leaks generation time. v4 is fully random — unpredictable and the most common choice in modern apps.

Are these UUIDs cryptographically secure?

Yes. Generated with crypto.randomUUID and crypto.getRandomValues from the Web Crypto API. Suitable for security-sensitive use cases.

How many UUIDs can I generate at once?

Up to 10,000 per batch. For more, run multiple batches or use a server-side library.

Is my data sent anywhere?

No. All UUIDs are generated in your browser. Nothing is sent to a server.

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