How to increase the execution timeout in php?

If you happen to be using Microsoft IIS server, in addition to the php.ini settings mentioned by others, you may need to increase the execution timeout settings for the PHP FastCGI application in the IIS Server Manager:

Step 1) Open the IIS Server Manager (usually under Server Manager in the Start Menu, then Tools / Internet Information Services (IIS) Manager).

Step 2) Click on the main connection (not specific to any particular domain).

Step 3) Under the IIS section, find FastCGI Settings (shown below).

Step 4) Therein, right-click the PHP application and select Edit....

Step 5) Check the timeouts (shown below).

In my case, the default timeouts here were 70 and 90 seconds; the former of which was causing a 500 Internal Server Error on PHP scripts that took longer than 70 seconds.

You had a typo: ini_set('max_input_time','200M') - value set needs to be an int, like ini_set('max_input_time','200')

optional : if you set config about php.ini but still can't upload

-this is php function to check error code

$error_type = [];
$error_type[0] = "There is no error";
$error_type[1] = "The uploaded file exceeds the upload_max_filesize directive in php.ini.";
$error_type[2] = "The uploaded file exceeds the MAX_FILE_SIZE directive that was specified in the HTML form.";
$error_type[3] = "The uploaded file was only partially uploaded.";
$error_type[4] = "No file was uploaded.";
//$error_type["5"] = "";
$error_type[6] = "Missing a temporary folder. Introduced in PHP 5.0.3.";
$error_type[7] = "Failed to write file to disk. Introduced in PHP 5.1.0.";
$error_type[8] = "A PHP extension stopped the file upload. PHP does not provide a way to ascertain which extension caused the file upload to stop; examining the list of loaded extensions with phpinfo() may help. Introduced in PHP 5.2.0.";
//------------------------------
//--> show msg error.
$status_code = $_FILES["uploadfile"]["error"];
if($status_code != 0){
    echo $error_type[$status_code];
    exit;
}

You can also set a max execution time in your .htaccess file:

php_value max_execution_time 180

To really increase the time limit i prefer to first get the current value. set_time_limit is not always increasing the time limit. If the current value (e.g. from php.ini or formerly set) is higher than the value used in current call of set_time_limit, it will decrease the time limit!

So what's with a small helper like this?

/**
 * @param int $seconds Time in seconds
 * @return bool
 */
function increase_time_limit(int $seconds): bool
{
    return set_time_limit(max(
        ini_get('max_execution_time'), $seconds
    ));
}

// somewhere else in your code
increase_time_limit(180);

See also: Get max_execution_time in PHP script