Mortar calculator

How much mortar do I need?

Estimate the number of 60-lb bags of mortar for brick or concrete block projects based on the number of units.

Mortar calculator

Mortar calculator result

Mortar mixing tips

Use a mortar mixing paddle and bucket for small batches. Add water gradually while mixing until the mortar reaches a peanut butter consistency. Mortar has a working time of about 2-3 hours, so mix only what you can use in that time. Keep mortar from freezing for 24-48 hours after application.

Worked example

For example, for 500 bricks, using Type S mortar:

  1. 500 bricks × 0.02 cu ft per brick = 10 cu ft of mortar
  2. 60-lb bags: 10 ÷ 0.75 = 13.3 → 14 bags needed
  3. For blocks: 500 blocks × 0.38 cu ft = 190 cu ft → 254 bags
  4. Add 1-2 extra bags for waste and buttering

Common mistakes

MistakeWhy it matters
Mixing too much at onceMortar sets in 1.5-2.5 hours — only mix what you can use in that time
Using the wrong mortar typeType N for above-grade walls, Type S for below-grade or retaining walls
Adding too much waterStiff mortar holds brick in place — wet mortar causes bricks to slide out of alignment