15 free UK DIY calculators

Work out what you need before you buy.

Fast, practical calculators for building, decorating, flooring, landscaping and home improvement. Enter your measurements, get an instant estimate and reduce guesswork before ordering materials.

Building & DIY calculators

Plasterboard Calculator

Calculate sheet quantities from wall dimensions, board size and waste allowance.

Calculate plasterboard

Stud Wall Calculator

Estimate vertical stud count and approximate timber length for a partition wall.

Calculate studs

Paint Calculator

Estimate litres of paint for a room using wall size, coats and paint coverage.

Calculate paint

Concrete Calculator

Calculate concrete volume for a slab, base or pad using metric measurements.

Calculate concrete

Brick Calculator

Estimate brick quantities from wall area, openings and a waste allowance.

Calculate bricks

Insulation Calculator

Estimate insulation area and the number of packs required from product coverage.

Calculate insulation

Flooring Calculator

Work out room area and packs of laminate or other packaged flooring.

Calculate flooring

Tile Calculator

Estimate wall or floor tile quantities from surface and tile dimensions.

Calculate tiles

Mortar Calculator

Estimate cement and sand quantities for a target mortar volume and mix ratio.

Calculate mortar

Gravel Calculator

Convert area and depth into cubic metres and approximate tonnes of aggregate.

Calculate gravel

Paving Slab Calculator

Estimate how many slabs are needed for a rectangular patio or path.

Calculate paving

Decking Calculator

Estimate linear metres and full board quantities from deck dimensions.

Calculate decking

Fence Panel Calculator

Estimate panel and post quantities for a straight fence run.

Calculate fencing

Roof Tile Calculator

Estimate roof tile quantities from roof area and tiles per square metre.

Calculate roof tiles

Screed Calculator

Calculate floor screed volume and approximate premixed bag quantities.

Calculate screed

Built for UK DIY projects

BuildCalcs UK uses metric measurements and common UK material sizes to make early-stage quantity planning faster. Every calculator runs directly in your browser, with no registration required.

Material coverage and installation requirements can vary by manufacturer and project. Use these tools as planning estimates and check product technical information before ordering or carrying out work.

Why calculate before ordering?

Buying too little can interrupt a project and create extra delivery costs, while buying too much can leave expensive surplus material. A quick estimate gives you a practical starting quantity that can then be checked against pack sizes, supplier guidance and the actual layout.