Mortar Calculator
Estimate mortar bags and cost using the units you will lay and your product’s coverage.
Start with a known brick or block count, or estimate it from wall dimensions and openings. Enter units laid per bag for the exact mortar product and application, add mortar waste once, and round up to whole bags. Imperial and Metric wall measurements describe the same project when you switch units.
The named coverage examples come from QUIKRETE Mortar Mix No. 1102 product data. They are upper coverage estimates for that 80 lb product and stated masonry, not guaranteed yields or a mortar-type recommendation. Use your supplier’s coverage for other units, joint dimensions, bedding methods, products or bag sizes, including kg bags. Bag weight alone does not establish coverage.
Count units that will actually be laid, excluding unused spare bricks or blocks. Add mortar waste once. The editable 10% default is a planning allowance. Core-fill grout, parging, stone veneer and repointing require separate estimates.
Your Estimate
Units to Lay
1000 units
Base Bag Equivalents
27.027 bags
Bag Equivalents with 10% Mortar Waste
29.730 bags
Mortar Bags to Purchase
30 bags
Bag equivalents display three decimals; purchasing uses the full unrounded calculation and rounds up only at the end. Cost covers the chosen mortar bags only, excluding masonry units, grout, tax, delivery, tools and labor.
Results Actions
Mortar bag coverage and worked examplesBrick wall takeoffConcrete block wall takeoff
Product Coverage Examples — Confirm Your Application
These named examples are upper coverage figures from the linked manufacturer data, not universal rates or a recommendation to use that mortar type. Verify coverage for your unit size, joint geometry, wall construction and bedding method.
How to Use the Mortar Calculator
- 1Choose a known unit count or the wall-area estimate. Count units to be laid, not unused spares purchased for breakage.
- 2For wall mode, enter wall length, height, total opening area, actual unit face dimensions and joint width. Use one masonry layer at a time.
- 3Choose a named coverage example only when it applies, or enter your supplier’s units-per-bag figure for the exact product and package.
- 4Enter a mortar waste allowance. Avoid adding waste again if your supplied rate already includes it.
- 5Optionally enter price per bag, then review the whole-bag purchase count and material cost.
Mortar Bag and Wall Takeoff Formulas
- 1Net wall area = wall length × height − total opening area.
- 2Estimated units to lay = net wall area ÷ [(actual unit length + joint) × (actual unit height + joint)], rounded up after converting to consistent area units.
- 3Base bag equivalents = units to lay ÷ units laid per bag.
- 4Total bag equivalents = base bag equivalents × (1 + mortar waste percentage ÷ 100).
- 5Purchase bags = total bag equivalents rounded up once. Do not round base bags before adding waste.
- 6Material cost = whole purchase bags × price per bag.
Example Calculation
For 1,000 standard bricks and a confirmed coverage of 37 bricks per bag, 1,000 ÷ 37 = 27.027 bag equivalents. With a selected 10% mortar waste allowance, 27.027… × 1.10 = 29.729…; buy 30 bags. At a hypothetical $9 per bag, material cost is $270. For 180 standard blocks at 13 blocks per bag and the same allowance, 180 ÷ 13 × 1.10 = 15.230…; buy 16 bags. These are separate product-coverage examples, not universal consumption rates.
Accuracy & Assumptions
- Coverage must match the exact product, bag size, masonry unit, joint width and depth, and bedding method. A wider joint needs a new applicable coverage rate; this calculator does not scale a generic volume rate.
- Wall mode uses actual face dimensions plus one bed and head joint width for a single masonry layer. Boundary joints, corners, bond and cut units require takeoff review.
- The wall estimate rounds to whole units before estimating mortar. Use known-count mode for a reviewed takeoff or the combined count from multiple sections.
- Opening area must be smaller than gross area. Wall dimensions and opening area convert together; coverage, waste and price remain unchanged when switching units.
- Bag equivalents are displayed to three decimals. Whole-bag rounding uses unrounded values.
- The tool does not infer mixed mortar volume from bag weight or specify a mortar type, strength or wall design.
- Cost is for mortar bags only. Masonry units, core grout, reinforcement, delivery, tax and labor are separate.
Frequently Asked Questions
How many bags of mortar do I need for 1,000 bricks?
At a confirmed 37 bricks per bag and 10% mortar waste, buy 30 bags. Replace the rate for your product and work; the named rate is an upper coverage example for QUIKRETE Mortar Mix No. 1102 in an 80 lb bag.
How many bags for 100 concrete blocks?
At 13 blocks per bag and a selected 10% mortar waste allowance, 100 ÷ 13 × 1.10 = 8.461…; round up to 9 bags. Confirm that coverage applies to the block dimensions, joint and bedding method.
Can I use 60 lb, 25 kg or other bag sizes?
Yes, with confirmed units laid per bag for that exact package and application. Select custom coverage and enter it. Do not assume coverage scales directly with bag weight or substitute a concrete-mix yield.
Does changing the mortar joint change bag coverage?
No. In wall mode it changes the estimated masonry-unit count. You must also supply coverage appropriate to the new joint geometry; unchanged units-per-bag coverage is not a prediction of wider-joint consumption.
Does the calculator subtract doors and windows?
Yes. Wall mode subtracts the combined opening area you enter. Use the same area units as the displayed wall system, and do not deduct openings again from a count already taken from plans.
Does this include block core-fill grout?
No. Mortar bonds masonry joints; grout filling hollow cells requires a separate estimate. Stone veneer, parging and repointing also need their own coverage basis.
What mortar type should I buy?
Use the type and product required by the project specification and masonry manufacturer. The example product is a coverage reference, not a suitability or structural-design recommendation.
This is a preliminary material estimate. Confirm the takeoff, product coverage, mortar compatibility and final order with your supplier or mason. Follow approved plans, applicable code and manufacturer installation instructions; this tool does not specify wall construction or mortar strength.