Interest can be measured by body language, little clues, big signals.
Look for the real message. As you meet, talk, stay in or go out, there are unspoken clues. One reaction is cool, distant. The other is right on target. He's really into you.
Contrast the body language in the following situations:
He is very nice, always pleasant, but usually stands back a little. Or, he moves closer the minute he sees you.
He seems remote, often looks around. Or, he leans toward you, smiling and eager. He angles his body toward you, listens intently.
When he talks he rubs his chin, drums his fingers, fiddles with his keys. Or, he stares right at you and later you catch him watching you.
He answers questions slowly, plays with his napkin at dinner, or lingers over converstions with others. Or, he speaks in a low intense voice and asks more questions of his own that are all about you.
He just nods when you meet in a group. You seem to be one of many that he talks to. Or, he gently takes your arm, to single you out, steering you away.
He politely helps you with your jacket or your chair covering all the social bases. Or, he takes every opportunity to be close, offering his hand, patting your shoulder, stealing a quick hug.
When you are out to dinner he may hum, slouch in his chair, stifle a yawn. He may frown when the waiter is slow and seem to rush thru his meal. Or, he chuckles and smiles, winking at you, laughing with you, taking the time to enjoy this special meal with you. He is clearly happy to be there.
Watch, listen, learn. Check all the body language cues. You will know if he's just being polite, or he's really into you.
Reading body language requires being perceptive and picking up on the cues being sent your way.
As a single woman, perfecting the skill of reading male body language is invaluable.