DataWeave 2.2 is compatible and bundled with Mule 4.2. Standard Support for Mule 4.2 ended on May 2, 2021, and this version of Mule will reach its End of Life on May 2, 2023, when Extended Support ends.

Deployments of new applications to CloudHub that use this version of Mule are no longer allowed. Only in-place updates to applications are permitted.

MuleSoft recommends that you upgrade to the latest version of Mule 4 that is in Standard Support so that your applications run with the latest fixes and security enhancements.

isNumeric(String): Boolean

Checks if the text contains only Unicode digits.

A decimal point is not a Unicode digit and returns false. Note that the method does not allow for a leading sign, either positive or negative.

Introduced in DataWeave 2.2.0. Supported by Mule 4.2 and later.


Name Description


The input string.


This example shows how isNumeric behaves with different inputs and sizes.


%dw 2.0
import isNumeric from dw::core::Strings
output application/json
  "a": isNumeric(null),
  "b": isNumeric(""),
  "c": isNumeric("  "),
  "d": isNumeric("123"),
  "e": isNumeric("१२३"),
  "f": isNumeric("12 3"),
  "g": isNumeric("ab2c"),
  "h": isNumeric("12-3"),
  "i": isNumeric("12.3"),
  "j": isNumeric("-123"),
  "k": isNumeric("+123")


  "a": false,
  "b": false,
  "c": false,
  "d": true,
  "e": true,
  "f": false,
  "g": false,
  "h": false,
  "i": false,
  "j": false,
  "k": false

isNumeric(Null): Boolean

Helper function for isNumeric so it works with null value.

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