The Perfect Concrete Mix Ratio for DIY Projects

Mixing your own concrete is one of the most empowering DIY skills you can learn — but get the ratio wrong and you'll end up with a crumbling mess. The good news? It's surprisingly simple once you know the numbers.

Why Mix Ratio Matters

Concrete is made of cement, sand, aggregate (gravel), and water. The ratio determines strength, workability, and durability. Too much water weakens the mix; too little cement leaves it brittle. For most DIY projects, a 1:2:4 ratio (1 part cement, 2 parts sand, 4 parts aggregate) is the gold standard.

Recommended Mix Ratios by Project

• Footings & foundations: 1:2:4 — High strength, standard for structural work
• Slabs & paths: 1:2:3 — Slightly richer cement for a smooth, durable finish
• Fence posts: 1:2:4 — Use a stiff mix (less water) for post-setting
• Countertops: 1:1.5:2 — Richer mix with finer aggregate for a glass-smooth surface
• Repair work: 1:2:2 — Higher cement content for fast curing and strong adhesion

The Water-to-Cement Rule

A 0.5 water-to-cement ratio by weight is ideal for most projects. For a standard 1:2:4 mix using one 94 lb bag of cement, you'll need roughly 5–6 gallons of water. Less water = stronger concrete, but harder to work. Err on the side of stiff.

Not sure how much concrete you need for your project? Our concrete calculator does the math instantly — just enter your dimensions.