Trench volume calculator.
Calculate trench excavation volume and face area for your drainage or utility run. Enter the length, base width and depth, & this trench volume calculator will find the trapezoidal face area and volume for each run, plus totals across every run. A shared side batter (0 for vertical sides) and working-space allowance for pipe-laying access apply to every run — not a substitute for a full excavation design. Output is bank-measure, convert with our Soil Bulking & Swell Factor calculator, or use our Truck Load & Haulage Calculator to size the muck-away job.
Drop an Excel or CSV file or to replace the table below.
Column A: run reference. Column B: length. Base width and depth (columns C and D) default to the values below if not supplied.
Parsed entirely in your browser — your file is never uploaded to our servers.
| Run | Length (m) | Base width (m) | Depth (m) | Face area (m²) | Volume (m³) | Row actions |
|---|---|---|---|---|---|---|
| — | — | |||||
| — | — | |||||
| — | — |
How we calculate this.
Calculate trench excavation volume and face area for your drainage or utility run. Enter the length, base width and depth, & this trench volume calculator will find the trapezoidal face area and volume for each run, plus totals across every run. A shared side batter (0 for vertical sides) and working-space allowance for pipe-laying access apply to every run — not a substitute for a full excavation design. Output is bank-measure, convert with our Soil Bulking & Swell Factor calculator, or use our Truck Load & Haulage Calculator to size the muck-away job.
For each run (row): cross-section is a trapezoid — bottom width = base width + 2 × working space, top width = bottom width + 2 × (depth × batter), face area = depth × (bottom width + top width) / 2, volume = face area × length. Batter and working space are shared across every run; totals sum every row's volume and length.
| Assumption | Value | Source |
|---|---|---|
| Default working space allowance | 0.3 m each side | Typical UK utility/pipe-laying access allowance — confirm against your project's method statement. |
| Default side batter | 1 (1:1, 45°) H:V ratio | User-adjustable, defaulted on rather than left at 0. Unsupported excavations in cohesive soil below roughly 1.2 m are commonly battered around 1:1 (45°); deeper or less stable ground typically needs temporary support rather than battering alone — see current excavation-safety guidance for your jurisdiction. Set it to 0 for a vertical-sided (supported) trench. |
This is an early-appraisal planning estimate, not a quotation or a substitute for a surveyed takeoff. Last reviewed 5 Aug 2026.
Enter the batter as a horizontal-to-vertical ratio — e.g. 1 means the trench widens by 1 m horizontally for every 1 m of depth, on each side. It defaults to 1 (1:1, 45°) — set it to 0 for a vertical-sided (supported) trench. It applies to every run in the table.
It varies by pipe size and jointing method — 300 mm each side is a common default for smaller utility pipes, but always check your project's method statement.
Yes — each row in the table is an independent run with its own length, base width and depth. Add rows for every run on the job, or upload a spreadsheet listing them all at once; totals sum every row.
Yes — click or drop an Excel (.xlsx/.xls) or CSV file onto the upload area. The first column should be an item name and the second the measurement for that row; extra columns this calculator uses are read too if present. The file is parsed entirely in your browser — it's never uploaded to our servers. Download the blank template first if you're not sure of the layout.
Yes — use the metric/imperial switch above the calculator. Values you've already entered convert automatically; nothing is lost switching back and forth.
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