How to filter a query on specific date format with MongoDB?

To filter a query on specific date format in MongoDB, use the $dateToString operator within an aggregation pipeline to convert dates to string format and then match against the desired date pattern.

Syntax

db.collection.aggregate([
    { $addFields: { stringDate: { $dateToString: { format: "%Y-%m-%d", date: "$dateField" } } } },
    { $match: { "stringDate": "YYYY-MM-DD" } },
    { $project: { "stringDate": 0 } }
]);

Sample Data

db.demo433.insertMany([
    { "DueDate": new Date("2019-11-23") },
    { "DueDate": new Date("2020-01-03") }
]);

{
    "acknowledged": true,
    "insertedIds": [
        ObjectId("5e771278bbc41e36cc3cae91"),
        ObjectId("5e771290bbc41e36cc3cae92")
    ]
}

Display all documents from the collection ?

db.demo433.find();

{ "_id": ObjectId("5e771278bbc41e36cc3cae91"), "DueDate": ISODate("2019-11-23T00:00:00Z") }
{ "_id": ObjectId("5e771290bbc41e36cc3cae92"), "DueDate": ISODate("2020-01-03T00:00:00Z") }

Example: Filter by Specific Date

Filter documents where DueDate matches "2020-01-03" in YYYY-MM-DD format ?

db.demo433.aggregate([
    { $addFields: { stringDate: { $dateToString: { format: "%Y-%m-%d", date: "$DueDate" } } } },
    { $match: { "stringDate": "2020-01-03" } },
    { $project: { "stringDate": 0 } }
]);

{ "_id": ObjectId("5e771290bbc41e36cc3cae92"), "DueDate": ISODate("2020-01-03T00:00:00Z") }

How It Works

• $addFields creates a temporary stringDate field with the formatted date string
• $dateToString converts the Date object to "YYYY-MM-DD" format using %Y-%m-%d
• $match filters documents where the string date equals the target value
• $project removes the temporary stringDate field from the final output

Conclusion

Use $dateToString in an aggregation pipeline to filter dates by specific string formats. This approach converts Date objects to strings for precise pattern matching while preserving the original date fields in results.