formula for getting gallons

[bboy aqua]

is there a formula using length,width and depth to get the amount of gallons cause im planning on building a pond pretty soon

 

[ghinksmon]

This link was previously posted.

http://www.ifocas.fsworld.co.uk/calculator.htm

For a pond, I believe it is cubic feet times 7.5. [ LxWxDx7.5] Confirm that elsewhere to be sure.