d ` l ` .

##  Examples

###  Using substr()

js

    
    
    const aString = "Mozilla";
    
    console.log(aString.substr(0, 1)); // 'M'
    console.log(aString.substr(1, 0)); // ''
    console.log(aString.substr(-1, 1)); // 'a'
    console.log(aString.substr(1, -1)); // ''
    console.log(aString.substr(-3)); // 'lla'
    console.log(aString.substr(1)); // 'ozilla'
    console.log(aString.substr(-20, 2)); // 'Mo'
    console.log(aString.substr(20, 2)); // ''
    

##  Specifications

Specification  
---  
[ ECMAScript Language Specification  
#  sec-string.prototype.substr
](https://tc39.es/ecma262/multipage/additional-ecmascript-features-for-web-
browsers.html#sec-string.prototype.substr)  
  
##  Browser compatibility

BCD tables only load in the browser  with JavaScript enabled. Enable
JavaScript to view data.

##  See also

  * [ Polyfill of ` String.prototype.substr ` in ` core-js ` ](https://github.com/zloirock/core-js#ecmascript-string-and-regexp)
  * [ ` String.prototype.slice() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/slice)
  * [ ` String.prototype.substring() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/substring)

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