Driveway area and sub-base estimator

Work out your driveway area and sub-base before you order

A driveway calculator that shows measured area, an explicit order allowance and sub-base volume. Enter supplier density for tonnes; the planning prompt covers England only.

Driveway area and sub-base estimate

Add non-overlapping areas at one depth. Tonnage needs supplier density; the planning prompt applies only in England.

Method and limitations

Model version: 2026-09-25-v6

  • Separate rectangles are added at one shared depth. Areas must not overlap; this calculator cannot detect overlap or confirm a site drawing.
  • Material volume uses the combined measured area and the explicit order allowance entered above.
  • No universal order allowance or separate compaction factor is assumed.
  • Tonnage is omitted unless you supply the selected aggregate's density.
  • The planning prompt compares measured area, before the allowance, with England's guidance for hard surfacing between the wall forming the dwellinghouse's principal elevation and a highway. It is not a planning decision.

What brought you here?

What happens next

  1. Measure the area in metres
  2. Confirm the surface and use the specified sub-base depth
  3. Enter an order allowance from your supplier or job specification, or use 0 for base quantity
  4. For front gardens in England, check area, surface and drainage against the planning guidance

Three useful starting points

Decision guides

This site calculates quantities and explains the rules. It does not quote prices, install driveways, or recommend a contractor.

Open the calculator