Free calculators for UK trades
Quick, accurate answers to the questions every job starts with — how many bricks, how much concrete, how many tonnes, how many rolls, what price. Built for UK materials, UK units and UK rates. 28 calculators, no signup, no fuss.
All 28 calculators
Structure
Brick Calculator
How many bricks for your wall — UK sizes, mortar bags and wastage.
Concrete Calculator
Slab and footing volumes in m³, with bag counts or ballast & cement.
Roof Pitch Calculator
Pitch in degrees, rise:run ratio and rafter length.
Mortar Calculator
Sand, cement and ready-mix bags for bricks or blocks.
Concrete Block Calculator
Blocks, mortar and wall ties for blockwork.
Groundwork
Aggregate Calculator
MOT Type 1, gravel, sand or topsoil — tonnes and bulk bags.
Gravel Calculator
Gravel, shingle and chippings in tonnes and bulk bags.
Outdoor
Decking Calculator
Boards, joists and screws for a timber or composite deck.
Turf Calculator
How many rolls of turf for your lawn, plus topsoil.
Block Paving Calculator
Paving blocks, sub-base and sand for a driveway or patio.
Fence Calculator
Panels, posts, gravel boards and postcrete for a fence run.
Topsoil Calculator
Topsoil in m³, tonnes and bulk bags for lawns and beds.
Postcrete Calculator
Bags of post mix per fence post, by hole and post size.
Interior
Plasterboard Calculator
Sheets, screws, scrim tape and jointing compound for walls and ceilings.
Paint Calculator
Litres of paint for walls and ceilings, by room size and coats.
Tile Calculator
Tiles, adhesive and grout for floors and walls, with wastage.
Stud Wall Calculator
Studs, plates, noggins and total timber for a partition wall.
Screed Calculator
Floor screed volume, sharp sand tonnage and cement bags.
Wallpaper Calculator
Rolls needed for a room, with pattern repeat handled properly.
Plaster Calculator
Bags of multi-finish, bonding or hardwall plaster.
Render Calculator
Sand, cement and coverage for scratch and top coats.
Flooring Calculator
Laminate packs, underlay rolls and the trims people forget.
Skirting Board Calculator
Lengths of skirting for a room, with mitre wastage.
Loft Insulation Calculator
Rolls of mineral wool for 270mm loft insulation.
Roofing
Pricing
Day Rate & Quote Calculator
Price a job from day rate, materials and markup — VAT included.
CIS Tax Calculator
CIS deductions on labour at 20% or 30%, materials excluded.
Hourly Rate Calculator
Work backwards from target take-home to the rate you need.
Why TradeCalcs?
Merchant websites bury their coverage tables in PDFs, and international converter sites do not know a bulk bag from a builder's bag. TradeCalcs is built around how UK trades actually buy materials and price work — metric measurements, 25kg and 850kg bags, MOT Type 1 densities, BS-standard brick and block sizes, and VAT at 20%.
Every calculator shows its working: the formula, the assumed dimensions or densities, and the rule-of-thumb conversions behind the answer. You can sanity-check the result instead of trusting a black box — which matters when you are ordering a lorry-load of something.
Common questions
Are the calculators free?
Yes — every one, with no signup, account or limits. The site is funded by advertising.
Are they for UK measurements?
Yes. Metres and millimetres, 25kg and 850kg bulk bags, MOT Type 1 densities, 215mm bricks, 440 × 215mm blocks and 20% VAT throughout.
How accurate are the results?
Every page shows its formula and assumptions. Treat results as ordering estimates — densities, bag yields and coverage vary by supplier, so confirm against your merchant's figures before you order.