UUID stands for Universally Unique Identifier. It is a 128-bit identifier formatted as 32 hexadecimal digits in groups: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx. Used to uniquely identify objects in software systems.

What is the difference between UUID v1 and UUID v4?

UUID v1 is time-based — generated from current timestamp and MAC address. UUID v4 is random — generated using random numbers. UUID v4 is preferred for privacy as it contains no device information.

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🆔 UUID Generator Online Free

Generate UUID v4 unique identifiers instantly. Single or bulk generation. Copy with one click. No signup, browser-based.

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UUID Generator Online Free — Generate Unique Identifiers Instantly

Our free online UUID generator creates Version 4 (random) and Version 1 (time-based) UUIDs instantly using your browser's built-in crypto API. Generate single UUIDs or bulk batches up to 100 at once. No signup, no server, completely private.

What is a UUID?

UUID (Universally Unique Identifier) is a 128-bit identifier formatted as: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx. With 2^122 possible values for v4, the probability of generating the same UUID twice is practically zero.

UUID v4 vs UUID v1

UUID v4: Completely random — recommended for most uses. Contains no device or time information.
UUID v1: Time-based — includes current timestamp. Can be sorted chronologically but reveals device information.

Common Uses for UUID

Database primary keys — unique row identifiers
API request IDs — trace requests across services
Session tokens — unique user sessions
File names — avoid naming conflicts
Distributed systems — unique IDs without central coordination

UUID vs GUID

GUID (Globally Unique Identifier) is Microsoft's term for UUID. They are identical 128-bit identifiers. GUID is used in .NET and Windows; UUID is used in other systems.

How to Use the UUID Generator

Choose UUID v4 (random) or UUID v1 (time-based) from the version selector
Click Generate to create a new UUID instantly
Click Copy to copy the UUID to your clipboard
For multiple UUIDs, enter a count and click Bulk Generate, then Copy All

Frequently Asked Questions

How do I generate a UUID online for free?

Click Generate UUID. A random UUID v4 is created instantly. Copy with one click. Bulk generation also available. Free.

What is a UUID?

128-bit unique identifier: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx. Used to uniquely identify objects in software systems.

What is the difference between UUID v1 and v4?

v1 is time-based (includes timestamp). v4 is random (no device info). v4 recommended for privacy and general use.

Is UUID guaranteed to be unique?

UUID v4 has 2^122 possible values. Probability of collision is astronomically low — practically guaranteed unique.

What is GUID vs UUID?

GUID is Microsoft terminology for UUID — they are identical 128-bit identifiers. Different name, same format.

🆔 UUID Generator Online Free

UUID Generator Online Free — Generate Unique Identifiers Instantly

What is a UUID?

UUID v4 vs UUID v1

Common Uses for UUID

UUID vs GUID

How to Use the UUID Generator

Frequently Asked Questions

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