Enter your measurements
Use metric or imperial inputs and deduct the openings that matter.
UK-first DIY quantity tools
Useful home-improvement calculators with clear assumptions, practical results and no guesswork. Check the formula before you buy.
Use natural language — try , or .
Estimates only. Calculator.Shop is not structural, compliance or professional construction advice.
Start with a real task
Estimate bricks or blocks for a wall, with opening deductions, waste and optional pack rounding.
Open calculator →02Walls & MasonryEstimate concrete or screed volume from a rectangular pour, with practical bag rounding.
Open calculator →03DecoratingWork out paintable wall area, litres and tins with coats, coverage and waste made explicit.
Open calculator →04DecoratingEstimate wallpaper rolls from wall dimensions, roll coverage, pattern repeat and waste.
Open calculator →A more useful way to plan
Use metric or imperial inputs and deduct the openings that matter.
Follow the audit path from measured area or volume to purchase quantity.
Copy a local summary or print it to keep with a shopping list or sketch.
Built for clarity
Calculator.Shop makes the assumptions visible rather than hiding them behind a single number. Every tool has a formula version, waste setting, audit trail and clear boundary around what it does not assess.
Read the methodology →Browse by project
Wall-faced materials and volume estimates with visible deductions and waste.
→DecoratingPlan paint and wallpaper quantities before you start a room refresh.
→Flooring & TilingSurface-covering quantities with pack rounding and practical material prompts.
→Outdoor ProjectsLoose materials, paving and boards for straightforward garden projects.
→Measurement ToolsReusable room and wall measurements to carry into other Calculator.Shop tools.
→Plan before you start
Use a calculator, then confirm the product guidance and your site measurements before ordering.