Lake Volume Calculator

Calculate lake volume in acre-feet, gallons, cubic feet, cubic yards, million gallons, liters, and cubic meters. Use this lake volume calculator for natural lakes, reservoirs, ponds, farm lakes, retention lakes, recreational lakes, water supply estimates, habitat planning, water treatment, and lake management.

Calculate Lake Volume

Lake Volume = Surface Area × Average Depth.
Your result will appear here.

How the lake volume calculator works

Surface area × average depth:
The calculator multiplies lake surface area by average depth to estimate volume.

Length × width × depth:
Enter lake length, average width, average depth, and shoreline shape factor to estimate surface area and volume.

Lake basin shape:
Use maximum depth and a basin shape factor to estimate volume when average depth is unknown.

Water level change:
Estimate how much water is gained or lost from a rise or drop in lake level.

Why use a lake volume calculator?

A lake volume calculator helps estimate how much water a lake holds for lake management, water supply, treatment, habitat planning, refill estimates, and water level tracking.

It can be useful for reservoirs, farm lakes, recreational lakes, retention lakes, wildlife lakes, natural lakes, stormwater ponds, irrigation lakes, and environmental planning.

What your result means

Your result shows estimated lake volume in acre-feet, gallons, million gallons, cubic feet, cubic yards, liters, cubic meters, water-level-change volume, sediment-adjusted volume, evaporation loss, refill time, and treatment amount.

Lake volume formulas

Frequently asked questions

How do you calculate lake volume?

Multiply lake surface area by average depth. If surface area is in acres and depth is in feet, the result is acre-feet.

How many gallons are in an acre-foot?

One acre-foot is about 325,851 gallons.

Should I use average depth or maximum depth?

Use average depth whenever possible. Maximum depth usually overestimates lake volume because lake bottoms slope and vary in depth.

How do I calculate volume from a lake level change?

Multiply the lake surface area by the change in water level. For example, a 1-foot drop over 25 acres equals about 25 acre-feet of water loss.