Excavation Volume Calculator

Excavation is where a project first reveals its surprises. The drawing says a hole, but the hole is three volumes at once: the soil that sits in the ground, the bigger pile of it once disturbed, and the smaller, compacted mass when you put it back. Order hauling on the wrong volume and you will pay for a second truck run; design a "balanced" cut and forget the swell, and you either export dirt or import it.

Excavation Volume Calculator works across the three ways earthmoving is actually measured — bank (in-place), loose (excavated) and compacted (placed) — for rectangular holes, sloped excavations, trenches and simple grade changes. Enter a side slope and it applies the trapezoidal prism formula that every basement, pool and footing dig really has. Then it converts your loose volume into truckloads and multiplies by a per-yard or per-load rate for a quick earthmoving budget.

The cut-and-fill tab handles levelling work directly: compare the volume you need to remove with the volume you need to place, and see whether the site balances or requires importing or hauling. Everything runs locally in your browser.

• Four dig shapes: Box (cube), sloped excavation (trapezoidal prism), trench and grade change, matching how real holes are made.
• Bank, loose & compacted: All three earthmoving volumes from your swell and compaction factors, in cubic yards, cubic metres and cubic feet.
• Side slopes: Enter the horizontal/vertical slope (e.g. 1.5:1) and the calculator expands the top footprint with wedge volumes automatically.
• Truck & hauling: Convert loose volume to loads on your truck capacity, with a per-load or per-yard rate for the budget.
• Cut & fill balance: Compare required cut vs available fill at different grades to see net import, export, or a balanced site.
• Rate estimates: Enter cost per cubic yard and see the excavation budget grow with your volume.
• Imperial or metric: Work in feet/inches or metres, with all three volume units reported together.
• Live estimate: Volume, trucks and cost update as you type, with the formulas shown step by step.
• Export: Copy or download the earthwork report as text, CSV or JSON.
• Learning guide: Swell and compaction tables, slope guidance, frost depth and earthmoving best practice.

1. Choose the dig shape. Box for a plain pit, Sloped for walls that batter back (basements, pools), Trench for pipe/footing runs, and Level for a simple grade change.
2. Enter length, width and depth. Use the average depth for uneven floors.
3. Set the side slope (sloped mode). 1.5:1 is typical for loose soil, 1:1 for firm ground, 0 for vertical walls.
4. Pick the soil type. The calculator sets a typical swell factor; adjust it for the material and moisture.
5. Set truck capacity. 10–17 cu yd for standard dump trucks, or your hauler's actual capacity.
6. Add the rate. Per cubic yard or per load to build a budget from your machine and haul costs.
7. For levelling, use cut & fill. Enter the cut depth and fill depth for the same area to see the net movement.
8. Read the estimate. Bank, loose and compacted volumes plus truckloads appear instantly.
9. Review the working. The maths shows the prism formula, slope wedges and swell conversion.
10. Export the report. Copy or download as text, CSV or JSON for the excavator or hauler.

Example 1 — Basement. A 30×20 ft basement dug 8 ft deep with 1.5:1 slopes: the plain box is 178 cu yd, and the slope wedges push the total to roughly 210 cu yd bank. At 1.25 swell that is ≈ 262 cu yd loose → about 15 loads in 17-cu-yd trucks.

Example 2 — Footing trench. A 60 ft × 2 ft × 3 ft trench (straight sides) holds 360 cu ft ≈ 13.3 cu yd bank. At 1.2 swell that hauls as 16 cu yd — slightly more than one 17-cu-yd load.

Example 3 — Balanced grade. Cut 4 in and fill 6 in over a 50×40 ft pad: cut is 24.7 cu yd, fill needs 37.1 cu yd (compacted), so the site must import about 12.4 cu yd net plus swell on the loose fill.

Example 4 — Pool. A 16×32 ft pool, 8 ft average depth, 1.5:1 side slopes: bank volume ≈ 150 cu yd, loose ≈ 188 cu yd at 1.25 swell, or ~11 loads of 17 cu yd each to haul the spoil.

Example 5 — Checking a quote. A contractor quotes 200 cu yd removed. The calculator at your dimensions says 178 cu yd bank / 223 cu yd loose — the loose number is what trucks carry, so the quote is believable once you know which one he meant.

• Three volumes, one tool: Bank, loose and compacted never get mixed up again — order and haul the right number.
• Slopes included: Real holes batter back; the calculator sizes the wedge, not just the box.
• Cut/fill balance at a glance: See whether you export, import or balance the site before the machine arrives.
• Budget-ready: Per-yard and per-load rates turn volume into a number you can price.
• Metric and imperial: Feet and metres both travel the same prism and swell maths.
• Explainable numbers: Every figure traces back to the formula, slope and swell in the working line.
• Export-ready: Text, CSV and JSON reports hand straight to the hauler or the invoice.
• Free and private: No uploads, no accounts, no logging.