Studies have shown that a crush usually lasts around 4 months, while love doesn't end over time.
Personally, I believe even the meaning of love can change depending on the person. For me, there are three types of love. 1.) Love, where the persons' happiness means more to you than your own. 2.) Familial love, where you love them because you have to, basically. They're your mom, or sister, or brother, whatever. Friends sometimes also fall under this category. 3.) "Mizo" (It's a word my fiancee and I made up to describe this.) It's the kind of love that most people call "true". You know deep down that you would die if this person died, that they are the world and mean more to you than anything. That when this person is in pain, you are. It's the kind of love that after three days you get the urge to run away and marry this person, and that feeling never fades. Time does not change Mizo, nor could any action or event. Mizo is a promise and a feeling and not completely understandable by anyone who has never felt it.
So how do you test it? Easy. Do you Mizo this person, would you die to save their life and would you go and marry this person right now and be happy for the rest of your life? If not, let's take a step down. Is this person family, or do you treat them like family? Would you get angry and storm away and fight with them like a sibling or parent? If not, how much does their happiness mean to you? If it means more than yours, than it's just love. If not, than you just like them.
I hope that helps a bit. But PenPhantom is also right, the only way to "test" love is time. Anything true and factual will be true and factual in 2 years, 5 years, and 10 years later...