Generate Unique Identifiers
In Milliseconds

The developer-friendly tool for creating RFC4122-compliant UUIDs. Secure, customizable, and always available.

Get ID Now

Client-Side Security

All IDs are generated locally in your browser. No data is ever sent to our servers.

Standard UUIDs

Generate RFC4122 v4 UUIDs. Customizable with hyphens, braces, and case options.

Go to UUID Generator →

GUID Format

Microsoft-style GUIDs pre-configured with uppercase and braces for registry/config use.

Go to GUID Generator →

Usage Recommendations

Category Recommended ID Reason
Internal Database (High Performance) Snowflake ID, BigInt, ULID, UUID v7 Optimized for indexing speed and storage efficiency.
Distributed Systems / Microservices Snowflake ID, UUID/GUID, PushID Prevents ID collisions when multiple servers generate data simultaneously.
Public API & User Facing (User Friendly) TypeID, NanoID, Sqids/Hashids Human-readable, URL-safe, and hides the actual record count.
High Security (Anti-Guessing) CUID2, NanoID Highly random and difficult for attackers to guess patterns.
Language Specific Optimization XID (Go), PushID (Firebase), MongoDB ObjectId Specially designed for performance within their specific ecosystems.

Choosing the Right ID

ID Type Size (Bit) Size (Byte) Best Use Case
UUID 128 bit 16 byte World standard. Suitable if your application is used by many people in various locations.
GUID 128 bit 16 byte Specifically if you are using Microsoft systems (Windows/SQL Server).
ULID 128 bit 16 byte Similar to UUID but sortable. Great for databases to keep search fast.
Snowflake ID 64 bit 8 byte Used by Twitter/Discord. Pure numbers, suitable for giant systems.
MongoDB ObjectId 96 bit 12 byte Must use if the database is MongoDB.
BigInt (64-bit) 64 bit 8 byte Sequential numbers (1, 2, 3...) for large-scale applications with massive data.
NanoID Variable Variable Suitable for short links (like bit.ly) or user-facing IDs.
Integer (32-bit) 32 bit 4 byte Simplest. Suitable for item IDs, user IDs, or small category data.
TypeID ~128 bit ~16 byte Modern ID with label (e.g. user_...). So programmers don't get confused what ID this is.
CUID2 Variable Variable Made specifically for modern web. Very secure, collision-resistant, and hard to guess.
Hashids Variable Variable Not a pure ID. Only hides real numbers (e.g. ID 1 becomes X9) so data count is hidden.
XID 96 bit 12 byte Special for Go language (Golang). Very fast for high-performance systems.
PushID 120 bit 20 byte Created by Firebase. Chronological IDs, keeping real-time data organized.
KSUID 160 bit 20 byte Most precise time ordering. Commonly used for giant system logs.
Sqids Variable Variable New version of Hashids. Can encode multiple numbers into one unique code.