Calculapedia

Mortar Calculator

How much mortar do you need? Enter your brick or block count.

Units to lay
Estimated cost
Shop mortar mix →

How this calculator works

A standard 70 lb bag of mortar lays roughly 125 bricks or 30 concrete blocks. The calculator divides your unit count by that rate and rounds up.

Worked example — 500 bricks:
500 ÷ 125 = 4 bags of mortar mix.

Joint size changes it

Thicker mortar joints use more mix. These figures assume a standard 3/8-inch joint; wider joints or hollow blocks filled with mortar will need more.

Frequently asked questions

How many bricks does a bag of mortar lay?

About 125 bricks per 70 lb bag with a standard joint.

How much mortar for concrete block?

Roughly one bag per 30 blocks.

Planning a concrete or masonry project

Material estimates are only one part of a masonry job. Check the product yield on the bag or supplier quote, allow for the shape of the site, and confirm delivery minimums before ordering. For structural work, follow local building requirements and get advice from a qualified professional.

How to use this estimate

Accuracy and limitations

Calculapedia provides educational planning estimates. It does not inspect your site, select products, guarantee quantities, or replace a contractor, engineer, architect, building official, or supplier. Confirm the final quantity and any safety or code requirements before buying or building.

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