How to return documents of a collection without objectId in MongoDB?

To return documents of a collection without objectId in MongoDB, use projection with _id:0 in the find() method. This excludes the automatically generated _id field from the query results.

Syntax

db.collection.find(query, { _id: 0 });

Sample Data

db.returnDocumentWithoutObjectId.insertMany([
    { "Name": "Carol", "Age": 25 },
    { "Name": "Sam", "Age": 21 },
    { "Name": "John", "Age": 23 }
]);

{
    "acknowledged": true,
    "insertedIds": [
        ObjectId("5ce8ba6c78f00858fb12e8fa"),
        ObjectId("5ce8ba6d78f00858fb12e8fb"),
        ObjectId("5ce8ba6f78f00858fb12e8fc")
    ]
}

Example 1: Default Query (With ObjectId)

First, let's see how documents appear with the default _id field ?

db.returnDocumentWithoutObjectId.find();

{ "_id": ObjectId("5ce8ba6c78f00858fb12e8fa"), "Name": "Carol", "Age": 25 }
{ "_id": ObjectId("5ce8ba6d78f00858fb12e8fb"), "Name": "Sam", "Age": 21 }
{ "_id": ObjectId("5ce8ba6f78f00858fb12e8fc"), "Name": "John", "Age": 23 }

Example 2: Exclude ObjectId

Now exclude the _id field using projection ?

db.returnDocumentWithoutObjectId.find({}, { _id: 0 });

{ "Name": "Carol", "Age": 25 }
{ "Name": "Sam", "Age": 21 }
{ "Name": "John", "Age": 23 }

Key Points

• The _id field is automatically included in all MongoDB queries by default.
• Use { _id: 0 } as the second parameter (projection) to exclude it.
• You can combine this with other field projections to control which fields are returned.

Conclusion

Use projection with _id: 0 in the find() method to return documents without the ObjectId field. This provides cleaner output when the _id field is not needed for your application logic.