How can I tell how many cfm's a fan is?

I am looking at the label for a fan that my brother has, he does not know how many cfm's this baby throws but it is pretty strong from feeling it. (It's an 80mm fan.) I look at the label on it and it doesn't literally say "cfm's" or anything of the sort. It says DC12V on it which I'm assuming means it's 12 volts and then it says "0.27 A," and I have no idea what that means. Is there any way for me to tell how many cfm's it throws from anything on the label? I'm looking to buy a few case fans and want something similar to these, airflow-wise.

well, the .27a means it draws 0.27 amps current-wise. That's about double from most generic case fans, so I'd say it's probably pretty strong. I believe you need some sort of meter to measure CFM accurately.

Does it have a monitoring wire to the motherboard? if it's about 3000rpms, it would be around 30-35 CFMs, etc...

RPMs are hardly a reliable indication of CFM...

Your best bet is to find the manufacturer of the fan and attempt to find it's twin online. If some reseller has them in stock, they'll likely have the technical details listed.

Well, if you know that it's a 80x25 @ a certain rpm you could compare it, well, yea it would never be close to precise but it's something if you cant find the specs..

If you can find a model number, enter it into google and do a search. That usally works for me.

Right there - look at the model number. For example my fan says NMB model: 4710nl etc so I searched google and the very first link returned was this one:

http://www.users.dircon.co.uk/~nmb/fans/4710nl/4710nl.htm

So I then looked at the rest of the model number and this told me that my fan - the 4710nl 04w b30 D00 - pushes about 70 cfm of air.

You should be able to do the same with your fan. Just look at the sticker on the fan hub.

yea teh smartest thing would be jsut to serach it up on google =d