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The do...while statement creates a loop that executes a specified statement until the test condition evaluates to false. The condition is evaluated after executing the statement, resulting in the specified statement executing at least once.

Syntax

do
   statement
while (condition);
statement
A statement that is executed at least once and is re-executed each time the condition evaluates to true. To execute multiple statements within the loop, use a block statement ({ ... }) to group those statements.
condition
An expression evaluated after each pass through the loop. If condition evaluates to true, the statement is re-executed. When condition evaluates to false, control passes to the statement following the do...while.

Examples

Using do...while

In the following example, the do...while loop iterates at least once and reiterates until i is no longer less than 5.

var result = '';
var i = 0;
do {
   i += 1;
   result += i + ' ';
} 
while (i > 0 && i < 5); 
// Despite i == 0 this will still loop as it starts off without the test

console.log(result);

Specifications

Specification
ECMAScript (ECMA-262)
The definition of 'do-while statement' in that specification.

Browser compatibility

Update compatibility data on GitHub
DesktopMobileServer
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung InternetNode.js
do...whileChrome Full support 1Edge Full support 12Firefox Full support 1IE Full support 4Opera Full support 4Safari 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

Document Tags and Contributors

Last updated by: fscholz,