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Version: 3.7.0


The setInterval() method, repeatedly calls a function or executes a code snippet, with a fixed time delay between each call.

This method returns an interval ID which uniquely identifies the interval, so you can remove it later by calling clearInterval().


setInterval(code, delay)

setInterval(func, delay)
setInterval(func, delay, arg0)
setInterval(func, delay, arg0, arg1)
setInterval(func, delay, arg0, arg1, /* … ,*/ argN)


  • func
    • : A function to be executed every delay milliseconds. The first execution happens after delay milliseconds.
  • code
    • : An optional syntax allows you to include a string instead of a function, which is compiled and executed every delay milliseconds. This syntax is not recommended for the same reasons that make using `eval() a security risk.
  • delay optional
    • : The time, in milliseconds (thousandths of a second), the timer should delay in between executions of the specified function or code. Defaults to 0 if not specified. below for details on the permitted range of delay values.
  • arg0, …, argN optional
    • : Additional arguments which are passed through to the function specified by func once the timer expires.

Return value

The returned intervalID is a numeric, non-zero value which identifies the timer created by the call to setInterval(); this value can be passed to clearInterval() to cancel the interval.

It may be helpful to be aware that setInterval() and setTimeout() share the same pool of IDs, and that clearInterval() and clearTimeout() can technically be used interchangeably. For clarity, however, you should try to always match them to avoid confusion when maintaining your code.

Note: The delay argument is converted to a signed 32-bit integer. This effectively limits delay to 2147483647 ms, since it's specified as a signed integer in the IDL.