Drag the points onto the real edges. Numbers update live.
Load a top-down photo of your excavation to trace it.
Rim at the top, floor at the bottom. Each layer has a depth below the rim and its own outline. The wall button sets how you reach a layer from the one above: shelf = vertical wall then a flat step in (a plant shelf), slope = angled wall down to it.
Acts on the layer selected above only, and leaves it exactly where it is. Fewer points are easier to drag on a phone; more give finer control. Halving discards detail permanently, doubling adds handles at the midpoints rather than bringing it back.
Turn on for a straight-down drawing or plan with no perspective. Scale still comes from the two spans; depths are whatever you type. No camera correction is applied.
Drag the purple cross to the spot on the ground directly under the camera. Anything below the rim photographs small and pushed away from that spot, and this undoes it. A drone shot from high up needs almost no correction, so set the real height.
Frozen, and set only from the two measured spans below. Never re-derived from the outline, so editing the trace moves area and volume the way it should. Volume goes as the cube of this, so 10% off here is 33% off on gallons.
Put each line exactly where you held the tape, type the real inches, then press from both. Two roughly perpendicular spans let it correct a foreshortened (angled) photo and honor both numbers at once. Watch Status flip from PROVISIONAL to "set from measured spans." One span alone gives a single uniform scale.
Autosave lives in this browser only. Save to file for a copy you can keep, move, or send back to me.