Suggested next steps
Continue this workflow
Move to a practical next or previous step without transferring your entered values.
About Mortar Calculator
Estimate required masonry mortar volume, commercial pre-mixed bags, or site-mix cement and sand quantities based on masonry unit count, joint thickness, and waste factor.
Inputs and calculations stay in your browser and require no signup.
How the calculation works
Planning calculation
Mortar volume = unit count × base yield per unit × (joint thickness / 0.375) × (1 + waste / 100). Pre-mix bags = ceil(adjusted volume / bag yield). Type N site mix: 1 bag Portland cement (94 lb) + 3 ft³ sand yields ~3.2 ft³ mortar.
How to use this calculator
- 1Enter measured project dimensions and quantities.
- 2Adjust material, spacing, waste or density assumptions to match the project.
- 3Review the live planning quantities.
- 4Round purchasing quantities appropriately and confirm field conditions.
Understanding the result
Standard modular clay bricks require approx 5.0 ft³ of mortar per 1,000 bricks at 3/8-inch joints. Standard 8x8x16 CMU concrete blocks require approx 13.5 ft³ of mortar per 100 blocks. 80-lb pre-mix bags yield approx 0.67 ft³.
Results use the units shown beside each field and output.
Important limitations
- Mortar yield varies by brick coring depth, frog impressions, and CMU face-shell bedding vs full bedding.
- Site-mixed mortar must adhere to standard ASTM C270 proportioning (Type N, S, or M) for required compressive strength.
- Weather conditions, evaporation, and joint tooling loss will alter field material consumption.
Explore this topic
Frequently asked questions
How many bags of mortar do I need for 1000 bricks?
For 1,000 standard modular bricks with 3/8-inch joints and 10% waste, you will need approximately 8 to 9 bags of 80-lb pre-mixed mortar mix.
How much mortar is needed for 100 cinder blocks?
For 100 standard 8x8x16 CMU concrete blocks with face-shell bedding, you need approximately 13.5 ft³ of mortar, which corresponds to roughly 22 to 24 bags of 80-lb pre-mix mortar.
What is the difference between Type N and Type S mortar?
Type N is a medium-strength mortar (approx 750 psi) used for general exterior above-grade walls and brick veneer. Type S is higher strength (approx 1,800 psi) used for below-grade foundations, retaining walls, and load-bearing CMU blocks.
Related tools
Selected from curated relationships first, then the same subtopic and category.