which resistor do I need for my LED?

What resistor is best for my single LED?  I've read that I need 1 Ohm (is that correct?), but I don't understand power watts and tolerance.  Could I get away without using a resistor at all?  Thanks.

battery voltage: 3
diode forward voltage: 2.8-3.4
diode forward current: 20mA

If the LED accepts 2.8 to 3.4V, then a 3V battery will not need any resistor.

Where did you get the 1Ohm value from? I'm guessing that an online calculator, and it just rounded up from ~0.

Good luck with your project.
I have.

battery voltage: 3
diode forward voltage 3.2-3.4
diode forward current: 20mA

is that going to work? What resistor do i need? Please help!
According to some of the better qualified people on here, you should still use the low value resistor to limit the current.