MongoDB $exp Operator (original) (raw)

Last Updated : 15 Jul, 2025

**MongoDB's aggregation **framework provides a powerful set of tools for **data manipulation and processing. One such tool is the **$exp**operator which allows users to perform exponential calculations within **aggregation pipelines. In this article, We will learn about the **MongoDB $exp Operator in detail.

MongoDB $exp Operator

The $exp operator in **MongoDB is used to raise the **mathematical constant **e (approximately **equal to **2.718) to the power of a given number.
It is commonly used in **mathematical computations and can be included in aggregation pipelines to perform exponential calculations.

**Syntax:

{ $exp: }

Here, the exponent is a valid expression until it resolves to a number.

If the entered value resolves to null, then this operator will return null.
If the entered value resolves to NaN, then this operator will return NaN.
If the entered value refers to a missing field, then this operator will return null.

**Examples of MongoDB $exp

In the following examples, we are working with:

**Database: GeeksforGeeks

**Collection: _example

**Document: two documents that contain the details of the shapes in the form of field-value pairs.

**Output:

**Example 1: Using $exp Operator

In this example, we are going to find the exponent of the value of the side field.

db.example.aggregate([ {$match: {name: "Square"}},
... {$project: {result: {$exp: "$side"}}}])

**Output:

**Example 2: Using $exp Operator in the Embedded Document

In this example, we are going to find the exponent of the difference of the values of **measurement.height and **measurement.width fields.

db.example.aggregate([ {$match: {name: "Rectangle"}},
... {$project: {result: {$exp:
... {$subtract: ["$measurement.height", "$measurement.width"]}}}}])

**Output:

Using-exp-Operator-in-the-Embedded-Document

Conclusion

The $exp operator in MongoDB is a useful tool for performing exponential calculations within aggregation pipelines. By raising e to a specified power, it facilitates complex mathematical computations in your MongoDB queries.