I needed this functionality for some high precision calculations I'm making. (autoit is not fast enough to support counting nanoseconds, sorry!) What's it do? It returns the number of microseconds past the current millisecond on the system clock. How accurate is it? Due to autoit limitations the counter will always be between 3-15 microseconds behind the system. ->*(This is how long autoit takes to initialize a counter) Example + UDF: _microsecinit() ;we HAVE to call this first to