Limited only by the amount of oxygen available to it.
Get a fire extinguisher! Or get LOTS of water!
Ok well dry leaves catch on fire fast because they contain no water and water repells against fire
Fire
It depends on the matirial, if the matirial is hard to be burned then the fire will not spread fast, and if it's a matirial that can be easily burned (such as wool) the fire will spread very fast.
Changes that take place within seconds are known as fast change. For example bursting of a fire cracker is a fast change and a forest fire can spread very fastly.
88.5 MPH
5mph
Fire growth rates are classified as slow, moderate, fast or ultra fast. Fires generaly have an exponential growth rate and the classification represents various times between flaming ignition and a fire delivering 1 MW of heat. 75 sec Ultra Fast 150 sec Fast 300 sec Moderate 600 sec Slow
Dragon Force Through The Fire and Flames is pretty fast
flyer
BURN
BURN