UUID vs MongoDB ObjectId — Comparison & Generator
Quick Answer: MongoDB ObjectId is 12 bytes (24 hex chars) with an embedded timestamp, similar to UUID v7. Use the default ObjectId for MongoDB-only systems. Use UUID when documents must have IDs compatible with other databases, APIs, or services outside MongoDB.
FAQ
Can I use UUID as MongoDB _id?
Yes. Set _id to a UUID string or use the native UUID BSON type (Binary subtype 4). The uuid package in your driver handles conversion.
What is the difference between ObjectId and UUID?
ObjectId is 12 bytes with a 4-byte timestamp. UUID is 16 bytes. ObjectId is time-sorted like UUID v7. UUID is a universal standard; ObjectId is MongoDB-specific.