Less than (<)

The less than operator (<) returns true if the left operand is less than the right operand, and false otherwise.

Syntax

 x < y

Description

The operands are compared using the Abstract Relational Comparison algorithm. See the documentation for the Greater than operator for a summary of this algorithm.

Examples

String to string comparison

console.log("a" < "b");        // true
console.log("a" < "a");        // false
console.log("a" < "3");        // false

String to number comparison

console.log("5" < 3);          // false
console.log("3" < 3);          // false
console.log("3" < 5);          // true

console.log("hello" < 5);      // false
console.log(5 < "hello");      // false

console.log("5" < 3n);         // false
console.log("3" < 5n);         // true

Number to Number comparison

console.log(5 < 3);            // false
console.log(3 < 3);            // false
console.log(3 < 5);            // true

Number to BigInt comparison

console.log(5n < 3);           // false
console.log(3 < 5n);           // true

Comparing Boolean, null, undefined, NaN

console.log(true < false);     // false
console.log(false < true);     // true

console.log(0 < true);         // true
console.log(true < 1);         // false

console.log(null < 0);         // false
console.log(null < 1);         // true

console.log(undefined < 3);    // false
console.log(3 < undefined);    // false

console.log(3 < NaN);          // false
console.log(NaN < 3);          // false

Specifications

Specification
ECMAScript (ECMA-262)
The definition of 'Relational operators' in that specification.

Browser compatibility

Update compatibility data on GitHub
DesktopMobileServer
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung InternetNode.js
Less than (a < b)Chrome Full support 1Edge Full support 12Firefox Full support 1IE Full support 3Opera Full support 3Safari Full support 1WebView Android Full support 1Chrome Android Full support 18Firefox Android Full support 4Opera Android Full support 10.1Safari iOS Full support 1Samsung Internet Android Full support 1.0nodejs Full support 0.1.100

Legend

Full support  
Full support

See also