Description The includes() method returns true if a string contains a specified string. Otherwise it returns false. The includes() method is case sensitive.

Nov 24, 2009 · Usually I would expect a String.contains () method, but there doesn't seem to be one. What is a reasonable way to check for this?

Jul 10, 2025 · The includes() method of String values performs a case-sensitive search to determine whether a given string may be found within this string, returning true or false as appropriate.

Oct 7, 2022 · The JavaScript includes() method was introduced with ES6, and it is the most common and modern way of checking if a string contains a specific character or a series of characters.

Feb 19, 2023 · This practical article walks you through 4 different ways to check whether a given string contains a substring or not. Without any further ado (like talking about the history of Javascript or …

Dec 5, 2025 · Learn how to check if a string contains a specific value in JavaScript using includes (), indexOf (), and regex. Simple examples for beginners.

In this tutorial, you will learn how to use the JavaScript String includes () method to check if a string contains a substring.

Feb 13, 2026 · Learn how to check if a string contains a substring in JavaScript using includes (), indexOf (), regex, and case-insensitive methods.

Learn how to use the JavaScript String includes () method to check if a string contains a specified substring. Explore syntax, examples, and practical applications.

What Does .includes() Do in JavaScript? The .includes() method allows you to check if a string contains another substring within it. For example: let str = "Hello world!"; Here, we check if str contains the …