Lay Smart, Buy the Right Amount

Paving Slab Calculator for UK Patio Projects

Avoid over-ordering or running short, this free paving slab calculator helps you figure out exactly how many slabs you need for your patio based on area, slab size, layout pattern, and grout joint width.

It also estimates how much sand and cement you’ll need for the sub-base and bedding layer. Plan smart and build with confidence.

📏 Paving Slab Calculator

Frequently Asked Questions

Use the calculator above by entering your patio area and slab size (including grout joints). It will tell you how many slabs you need, including a waste buffer based on your chosen layout.

Yes — always allow 5–15% extra for cutting, breakages, and pattern layout. The calculator automatically adds this based on your chosen layout pattern.

For a typical 50mm bedding layer using a 5:1 dry mix, you’ll need around 50–75 kg of sand and 25 kg of cement per m². The calculator estimates totals for your full patio.

Stacked and stretcher bond layouts are easiest and most efficient. Random layouts require more cutting and waste but offer a more natural, varied look.

Yes, just enter the dimensions of your slab. For mixed sizes (random patterns), use the average size, or consult your supplier for a pack coverage rate.