JavaScript RangeError - Repeat count must be non-negative Last Updated : 15 Jul, 2025 Comments Improve Suggest changes Like Article Like Report This JavaScript exception repeat count must be non-negative occurs if the argument passed to String.prototype.repeat() method is a negative number. Message: RangeError: argument out of range RangeError: repeat count must be non-negative (Firefox) RangeError: Invalid count value (Chrome) Error Type: RangeError Cause of Error: The repeat() method has a parameter that indicates the number of times to repeat the string. It should be in the range 0 to Infinity and cannot be a negative number. Example 1: In this example, the parameter's value passed is a negative value, So the error has occurred. JavaScript 'GFG'.repeat(-1); // error here Output(in console): RangeError: Invalid count value Example 2: In this example, the parameter's value passed is a negative value, So the error has occurred. JavaScript let gfg = "This is GeeksforGeeks"; gfg.repeat(-100); // error here Output(in console): RangeError: Invalid count value Comment More infoAdvertise with us Next Article Introduction to JavaScript P PranchalKatiyar Follow Improve Article Tags : JavaScript Web Technologies JavaScript-Errors Similar Reads JavaScript Tutorial JavaScript is a programming language used to create dynamic content for websites. It is a lightweight, cross-platform, and single-threaded programming language. It's an interpreted language that executes code line by line, providing more flexibility.Client Side: On the client side, JavaScript works 11 min read JavaScript BasicsIntroduction to JavaScriptJavaScript is a versatile, dynamically typed programming language that brings life to web pages by making them interactive. 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