Pond Tools

Stop guessing your gallons.

Get a precise estimate of your pond's volume with a few simple measurements. Plan complex shapes before you dig, keep track of your progress as you go, and build a perfect home.

Measure a pond
Free · nothing to install · runs in your browser
0" 12" 34" 28 17 22 9 0 24"
Three steps

A tape measure, a photo, and about five minutes.

01 — PHOTOGRAPH

Shoot straight down

One overhead photo of the excavation. Phone held flat, or a drone if you have one. Higher is better, because less of the depth gets pushed sideways by the lens.

02 — MEASURE

Two spans with a tape

Pull a tape across the rim twice, roughly at right angles, and type both numbers in. That is the only real-world scale the tool needs, and it is what makes the answer trustworthy.

03 — TRACE

Drag the outlines

Drop points around the rim, each shelf, and the floor, then enter how deep each one sits. Add as many ledges as your pond actually has. Gallons update as you drag.

Why the number holds up

It corrects the things that quietly wreck a photo estimate.

Foreshortening. Shoot at any angle and one axis of your pond compresses. Give the tool two measured spans and it solves a separate scale for each axis, so both of your numbers come back exactly right instead of being averaged into something that fits neither.

Depth parallax. Anything below the rim sits further from the lens, so it photographs smaller and displaced outward from the point under the camera. That is relief displacement, straight out of aerial photogrammetry, and it is undone using your camera height.

Stepped walls. Ponds are not cones. Every shelf is modelled as its own outline at its own depth, with a vertical wall or an angled one, and the volume is integrated layer by layer.

Nothing is uploaded to size your pond, and there is no account. If you have a salinity meter, the salt-dilution method is a good independent cross-check; the gap between the two is roughly the volume your rock and liner displace.

Chart key
Rim to first shelf
Shelf to slope
Floor of the deep section
Traced contour
34″ Depth below rim
The chart above is a real pond: 195″ around the rim, a 12″ planting shelf, and a floor 34″ down.