diff --git a/src/wp-includes/load.php b/src/wp-includes/load.php
index be5a8fcda7..0ea926c9dd 100644
--- a/src/wp-includes/load.php
+++ b/src/wp-includes/load.php
@@ -333,6 +333,19 @@ function wp_is_maintenance_mode() {
 	return true;
 }
 
+/**
+ * Get the time elapsed so far during this PHP script.
+ *
+ * Uses REQUEST_TIME_FLOAT that appeared in PHP 5.4.0.
+ *
+ * @since 5.8.0
+ *
+ * @return float Seconds since the PHP script started.
+ */
+function timer_float() {
+	return microtime( true ) - $_SERVER['REQUEST_TIME_FLOAT'];
+}
+
 /**
  * Start the WordPress micro-timer.
  *