10 × 2.5 m wall with a 2 m² door
50 × 20 cm blocks, 1 cm joints, 5 % margin: 23 m² net, 9.34 blocks/m², 226 blocks, about 362 L of mortar and 4 bags of cement.
Block and brick calculator
Enter the wall size, the openings to deduct and the block format: PRAXAO calculates the number of blocks or bricks with a breakage margin, the mortar volume and the cement bags to buy.
What do you want to calculate?
Choose the type of work, then enter the dimensions.
Results are provided for information. Check tax rates and legal requirements that apply to you.
How to use it
- Enter the wall length and height, or its area directly.
- Deduct the openings (doors, windows) in m².
- Enter the block size in centimetres and the joint in millimetres.
- Adjust the mortar per m² and the cement dosage to your practice.
Examples
Frequently asked questions
How many blocks per m²?
With 50 × 20 cm blocks and 1 cm joints, about 9.3 per m². The calculator uses your block size and joint, so it also works for bricks.
How much mortar does a block wall need?
Roughly 10 to 25 litres per m² depending on the block thickness and the joints. Hollow blocks laid with thin joints need less.
Should I deduct doors and windows?
Yes, deduct the openings, but keep the breakage margin: cuts around openings and lintels create waste.
Can I place windows and doors in the drawing?
Yes: choose “Wall with openings”, enter the number and size of windows and doors, and the calculator deducts their exact area. The drawing shows the 3D wall, the elevation with the block bond, the plan and two sections. Openings are spaced evenly in the drawing: their position does not change the quantities, only their area does.
Guides to go further
BUILIVA
How many blocks and how much mortar for a wall
Net area, blocks per m², mortar, cement bags and waste: the method with an example.
BUILIVA
How to calculate plaster and render for a wall
Net area, coat thickness, waste margin, then mortar, cement and sand: the method to order the right quantity of render, with a worked example.
Next step
- Turn this calculation into a quoteCarry the quantities into a priced quote, ready to send to your client.
- All tools in the “Walls & masonry” category
Related tools
BUILIVA
Reinforced Concrete
Column, footings and beam: concrete, formwork with or without, pours, stripping and bars by mark, stirrups, starter bars and meshes.
BUILIVA
Rebar: Weight and Bending
Rebar weight from a length or cut pieces, plus cut length and weight of stirrups, L, U and straight bars, with hooks, waste and 12 m bars to buy.
Quote Generator
Prepare a clear quote or estimate for your client, with validity date, taxes and totals, ready as PDF.