Terminates a function and return a value from a function to the calling function, if the function has non-void return type.


// from within a "void" function:

// from within a non-"void" function:
return value;

In the second case, value should have a type which is the same as the return type of the function, or be convertible to it (like an int to a double, etc.; see this note for some references).


A function to compare a sensor input to a threshold:

 // converts analog readings between 0 and 400 to 0, and 400 up to 1.
 int checkSensor() {
    if (analogRead(0) > 400) {
        return 1;
    else {
        return 0;

An early return is also useful when testing a section of code without having to “comment out” large sections of possibly buggy code, like so:

void loop() {

    // brilliant code idea to test here


    // the rest of a dysfunctional sketch here
    // this code will never be executed

See Also

License and Attribution

Portions of this page were adapted from the Arduino Reference Documentation, which is released under a Creative Commons Attribution-ShareAlike 3.0 License.