Howto: Address Google reCAPTCHA v3 not stopping as effectively as expected

If you have Google reCAPTCHA version 3 (Invisible version), and you feel like spam submissions are getting through more than they should, you can make use of an available filter to adjust the version 3 threshold for acceptance.

By default, the threshold is at a value of 0.5. To make criteria more strict, try increasing closer to 1.0.

The following snippet can be put into your active theme’s functions.php file or anywhere where filter callbacks can be stored, like via a code embed plugin.

function ctct_support_increase_recaptcha_threshold( $threshold, $form_id ) {
	// $form_id will be the numeral ID associated with the current form being submitted to,
	// and can be used to conditionally apply the new threshold value to. For our snippet,
	// we will affect all of the forms.
	
	return 0.8;
}
add_filter( 'constant_contact_recaptcha_threshold', 'ctct_support_increase_recaptcha_threshold', 10, 2 );