String.prototype.bold()

Deprecated: This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.

The bold() method of String values creates a string that embeds this string in a element (str), which causes this string to be displayed as bold.

Note: All HTML wrapper methods are deprecated and only standardized for compatibility purposes. Use DOM APIs such as document.createElement() instead.

js
const contentString = "Hello, world";

document.body.innerHTML = contentString.bold();

This will create the following HTML:

html

Hello, world

Instead of using bold() and creating HTML text directly, you should use DOM APIs such as document.createElement(). For example:

js
const contentString = "Hello, world";
const elem = document.createElement("b");
elem.innerText = contentString;
document.body.appendChild(elem);

Specifications

Specification

ECMAScript® 2027 Language Specification
# sec-string.prototype.bold

Browser compatibility

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Standard built-in objects
String
Constructor
1. String()
Static methods
Instance methods
Instance properties
1. length
Inheritance
Object/Function
Static methods
Static properties
Instance methods
Instance properties
1. __proto__
2. constructor

String.prototype.bold()

In this article

Syntax

Parameters

Return value

Examples

Using bold()

Specifications

Browser compatibility

See also

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