Mortar Calculator
Estimate bags of mortar for block or brick.
Enter how many blocks or bricks you're laying and pick the unit type to estimate the bags of mortar mix needed. Mortar use varies with joint size and waste, so treat this as a planning figure and buy a little extra.
How it works
As a rule of thumb, about 3 bags of mortar lay 100 standard blocks, and about 7 bags lay 1,000 modular bricks. Joint thickness, mix type, and waste all affect the real amount, so round up and keep a spare bag on hand.
Frequently asked questions
How much mortar do I need?
About 3 bags per 100 blocks, or about 7 bags per 1,000 bricks. For 100 blocks, plan on roughly 3 bags.
How many blocks does a bag of mortar lay?
Roughly 33 standard blocks per bag, depending on joint size and mix type.
Should I buy extra mortar?
Yes — mortar use varies with joint thickness and waste, so round up and keep a spare bag.
Is this calculator free and private?
Yes. Every CubicCabin calculator runs entirely in your browser, so the numbers you enter are never uploaded or stored. There's no sign-up, no limits, and it keeps working even if you lose connection after the page loads.