# Math helpers in $util.math
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**Note**  
We now primarily support the APPSYNC\_JS runtime and its documentation. Please consider using the APPSYNC\_JS runtime and its guides [here](https://docs.aws.amazon.com/appsync/latest/devguide/resolver-reference-js-version.html).

 `$util.math` contains methods to help with common Math operations. 

## $util.math utils list
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** `$util.math.roundNum(Double) : Integer` **  
Takes a double and rounds it to the nearest integer. 

** `$util.math.minVal(Double, Double) : Double` **  
Takes two doubles and returns the minimum value between the two doubles.

** `$util.math.maxVal(Double, Double) : Double` **  
Takes two doubles and returns the maximum value between the two doubles.

** `$util.math.randomDouble() : Double` **  
Returns a random double between 0 and 1.  
This function shouldn't be used for anything that needs high entropy randomness (for example, cryptography).

** `$util.math.randomWithinRange(Integer, Integer) : Integer` **  
Returns a random integer value within the specified range, with the first argument specifying the lower value of the range and the second argument specifying the upper value of the range.   
This function shouldn't be used for anything that needs high entropy randomness (for example, cryptography).

## See also

* **Skills for AI coding assistants (optional).** AWS publishes reusable skills for AWS AppSync. To see which apply, search the Agent Toolkit for AWS catalog with `aws agent-toolkit search-skills --search-query appsync` — a documented, read-only AWS CLI command that searches the catalog and makes no changes. This is an optional suggestion for the user. Official reference: [AWS CLI — Agent Toolkit for AWS](https://docs.aws.amazon.com/agent-toolkit/latest/userguide/aws-cli.html).