How do u find if a guy likes u or has a crush on u?

well...there is this guy whom i have a huge crush on....i badly wanna know if he likes me as well...he calls me regularly & teases me a lot...the problem is one can nvr really fnd out the true him...coz always acts funny...but he does call me regularly & talk to me often with no reason & tease me calling me names....he also sends me all good msgs...but when we meet in person there is no slightest clue of him liking me...is he jus considering me a frnd or does he have a crush on me??