Concrete Mix Calculator
Your estimate
- Cement weight
- 685 lb311 kg
- Sand
- 0.56 yd³15.2 ft³ · 0.43 m³
- Sand weight
- 0.76 tons1,523 lb · 0.69 t
- Gravel
- 0.85 yd³22.9 ft³ · 0.65 m³
- Gravel weight
- 1.07 tons2,141 lb · 0.97 t
- Water
- 41,057.3 gal155,418.7 L
- Concrete (with waste)
- 1.1 yd³29.7 ft³ · 0.84 m³
For mixing concrete yourself from cement, sand and gravel — also answers “how much cement do I need”.
Updated 2026-10-20 · Based on: bag yields printed by concrete-mix makers (0.30–0.60 ft³ per bag) and a 1.54 dry-volume factor.
How to use the Concrete Mix Calculator
- Enter the volume of concrete, or switch to Dimensions.
- Pick the mix ratio: 1:2:3 for general work, 1:2:4 for footings and slabs, 1:1.5:3 for strong work.
- Choose your cement bag size.
- Read the cement bags, sand, gravel and water.
Formula
Dry materials shrink when water is added, so the dry volume is 1.54 × the wet volume.
Each part = dry volume × part ÷ sum of parts. Cement weighs about 1,440 kg/m³ (94 lb per ft³ bag); water ≈ half the cement weight (water–cement ratio 0.5).
Worked example
With the values preset in the calculator above: (Volume)
- Volume
- 1 yd³
- Mix (cement : sand : gravel)
- 1 : 2 : 3 — general use
- Cement bag
- 94 lb bag
- Extra for waste
- 10 %
- Cement bags
- 8
- Cement weight
- 685 lb (311 kg)
- Sand
- 0.56 yd³ (15.2 ft³)
- Sand weight
- 0.76 tons (1,523 lb)
- Gravel
- 0.85 yd³ (22.9 ft³)
How much cement do I need for one cubic yard?
With a 1:2:3 mix one cubic yard needs 7 bags of 94 lb portland cement (623 lb), 0.51 yd³ of sand and 0.77 yd³ of gravel.
Related guides
Frequently asked questions
What is the best concrete mix ratio?
1:2:3 (cement : sand : gravel) is a good all-round mix. Use 1:2:4 for footings and mass concrete, 1:1.5:3 when you need extra strength.
How much water do I add?
About half the weight of the cement — for a 94 lb bag roughly 5–6 gallons. Too much water weakens concrete.
Is a bag of portland cement the same as concrete mix?
No. Portland cement is only the binder; you still add sand and gravel. Pre-mixed concrete bags already contain all three.
More calculators
Estimates only — check quantities with your supplier and local building code before you order.