Concrete Calculator 2026

How to Estimate Concrete for Any Project in 2026

Ordering concrete is a one-shot decision: order too little and you get a cold joint and a short-load fee on the second truck; order too much and you're paying $130–$190 per wasted yard. This calculator does the volume math for slabs, footings, columns, and walls, converts it to cubic yards and bag counts, and prices it with current 2026 regional ready-mix rates — including the 10% waste factor every experienced contractor builds in.

The Math Behind the Calculator

Concrete is sold by the cubic yard (27 cubic feet). For a rectangular slab, the formula is: length (ft) × width (ft) × thickness (ft) ÷ 27 = cubic yards. A 10×10 patio at 4 inches deep works out to 100 × 0.333 ÷ 27 = 1.23 yd³ — call it 1.4 yd³ after waste. Footings use the same volume math per linear foot; columns use πr²h. The calculator handles each shape and rounds to ordering increments.

Bags vs. Ready-Mix: The 0.5-Yard Rule

For small jobs, bagged concrete wins. An 80 lb bag yields about 0.60 ft³, so a cubic yard takes roughly 45 bags — at $6–$8 per bag, that's $270–$360 per yard plus your labor mixing it. Ready-mix runs $130–$190 per yard delivered, but trucks charge short-load fees ($50–$150) for orders under about 8 yards. The crossover: under half a yard, use bags; above it, price both. This calculator shows bag counts (40, 60, and 80 lb) alongside truck yardage so you can compare directly.

2026 Regional Pricing

Ready-mix prices vary more by region than by PSI rating. In 2026, the national average for 3,000 PSI mix is $130–$190/yd³ delivered. The Northeast and West Coast run $160–$200; the Southeast and Midwest $120–$150. Higher-strength 4,000–5,000 PSI mixes add $10–$25/yd³. Fuel surcharges, weekend delivery, and pump truck rental (for backyard pours without truck access — $800–$1,200/day) all stack on top. Use the region selector above to localize your estimate.

Thickness, PSI, and Reinforcement — Getting the Spec Right

The right slab spec depends on the load it carries. Patios and walkways: 4 inches at 3,000 PSI with wire mesh. Driveways: 5–6 inches at 3,500–4,000 PSI with #3 or #4 rebar on a 12–18 inch grid. Garage floors: 5–6 inches at 4,000 PSI. Anything carrying trucks or equipment: 6–8 inches with engineered reinforcement. Going from 4 to 6 inches raises material cost 50% — which is exactly why you should run both thicknesses through the calculator before committing, and always check local building code minimums.

Site Prep and Pour-Day Checklist

Volume is only half the job. Before the truck arrives: excavate to depth plus 4 inches for the gravel base, compact 4 inches of crushed stone, set forms with stakes every 3–4 feet, install reinforcement on chairs (not lying on the base), and have at least two people ready — a yard of concrete weighs about 4,000 pounds and starts setting in 90 minutes. In hot weather, pour early morning; below 40°F, use cold-weather blankets or wait. The calculator's waste factor covers spillage and uneven subgrade, but it can't fix unprepared forms.