Official battery testing technique!?

[Tom]

Its not a blatantly obvious battery good or battery bad though. It starts the car fine but sometimes it motors over and sort of splutters for a second before it actually starts, where as i know it should be turn the key and it should start almost instantly. Which i think is it not quite turning over fast enough could be the battery could be the starter but because its so slight/subtle its hard to find the bad component because everything does technically work. Just something isnt 100%.