Show the math
- Convert to feet (inches ÷ 12, centimeters ÷ 30.48): Length 24 ft; Width 12 ft; Thickness 5 in = 0.4167 ft
- Volume = 24 × 12 × 0.4167 × 1 = 120 ft³
- Net volume = 120 ft³ ÷ 27 = 4.4444 yd³ (× 0.0283168 = 3.398 m³)
- Order quantity = 4.4444 yd³ × (1 + 10%) = 4.8889 yd³ = 132 ft³
- 80 lb bags = 132 ft³ ÷ 0.6 ft³ per bag = 220 → 220 bags (always round up)
- Weight = 132 ft³ × 150 lb/ft³ = 19,800 lb
How to measure
Measure the finished width at several points because driveways often flare at the street or widen into a parking pad. Break an irregular driveway into rectangles, calculate each one, then add them in the Pour List. A curved apron can be treated as a rectangle with the average width.
Thickness is the dimension to confirm with your contractor. A passenger-car driveway is commonly 4 to 5 in; heavier loads such as trucks, RVs and garbage trucks call for 6 in or more with reinforcement.
Worked example: a 12 × 24 ft driveway at 5 in
- Convert to feet (inches ÷ 12, centimeters ÷ 30.48): Length 24 ft; Width 12 ft; Thickness 5 in = 0.4167 ft
- Volume = 24 × 12 × 0.4167 × 1 = 120 ft³
- Net volume = 120 ft³ ÷ 27 = 4.4444 yd³ (× 0.0283168 = 3.398 m³)
- Order quantity = 4.4444 yd³ × (1 + 10%) = 4.8889 yd³ = 132 ft³
- 80 lb bags = 132 ft³ ÷ 0.6 ft³ per bag = 220 → 220 bags (always round up)
- Weight = 132 ft³ × 150 lb/ft³ = 19,800 lb
| Quantity | Result |
|---|---|
| Net volume | 4.444 yd³ (120.00 ft³, 3.398 m³) |
| Order with 10% waste | 4.89 yd³ (3.74 m³) |
| 80 lb bags | 220 |
| 60 lb bags | 294 |
| Weight at 150 lb/ft³ | 19,800 lb |
That is 4.89 yd³. At a typical ready-mix range of $125–$195 per yard the concrete itself is about $661–$1,353 including delivery assumptions. Add forming, base, reinforcement and finishing; for installed prices contractors quote per square foot, not per yard.
How much does width and thickness change the order?
| Width | 4 in | 5 in | 6 in |
|---|---|---|---|
| 10 ft | 3.26 yd³ | 4.07 yd³ | 4.89 yd³ |
| 12 ft | 3.91 yd³ | 4.89 yd³ | 5.87 yd³ |
| 16 ft | 5.21 yd³ | 6.52 yd³ | 7.82 yd³ |
| 20 ft | 6.52 yd³ | 8.15 yd³ | 9.78 yd³ |
| 24 ft | 7.82 yd³ | 9.78 yd³ | 11.73 yd³ |
Moving from 5 to 6 in on the single-car driveway raises the order from 4.89 to 5.87 yd³, an increase of 0.98 yd³. A double-wide 20 ft driveway of the same length needs 8.15 yd³.
What goes under and into a driveway
The concrete is only part of the job. Most driveways sit on a compacted aggregate base, commonly 4 in or more, which is calculated with the gravel base calculator. Reinforcement is usually welded wire mesh or rebar on a grid; the rebar calculator shows quantities for a given spacing. Joints cut or tooled at roughly 24 to 36 times the slab thickness control cracking, which is 10 to 15 ft for a 5 in slab (ACI 302.1R).
Edges that take wheel loads sometimes need to be thickened. Ask the contractor or engineer. The thickened edge adds concrete, which you can add with the footing calculator.
Ordering a driveway pour
- Order about 5 to 10% more than the net volume.
- Ask the plant for a mix suited to exterior flatwork, commonly with air entrainment where freeze-thaw cycles occur. See the PSI guide.
- Check truck access: a loaded mixer is heavy and can damage a lawn or a thin curb. A pump may be needed.
- Have finishers and tools ready before the truck arrives. Concrete does not wait.
- Read how to order ready-mix concrete for the checklist.
Common driveway mistakes
- Measuring at a single spot when the width changes.
- Using the same thickness for a driveway and a patio without thinking about vehicle loads.
- Forgetting the apron at the street, which may be regulated and thicker.
- Skipping the base and ordering concrete to fill whatever dips remain.
- Pouring in very hot or very cold weather without preparation.
Next steps
Use the Project Kit under the result to estimate rebar, gravel and cost, or the concrete cost calculator to compare a truck with bags. For other flatwork see the patio calculator and the sidewalk calculator.
Frequently asked questions
How many yards of concrete for a driveway?
A 12 × 24 ft driveway at 5 in thick is 120 ft³, or 4.44 yd³ before waste. With 10% waste, order about 4.9 yd³.
How thick should a concrete driveway be?
Four inches is a common minimum for cars and light trucks, five to six inches is better for heavier vehicles. Your local code and soil conditions govern.
How much does a concrete driveway cost?
The concrete material is a fraction of the installed price. Contractor quotes include base, forms, reinforcement, finishing, curing and labor, usually priced per square foot. Get several local quotes.
Can I pour a driveway with bagged concrete?
Only a small one. A 12 × 12 ft apron at 5 in with 10% waste needs about 110 bags of 80 lb mix. A full driveway is a ready-mix job.
What PSI for a driveway?
Many plants supply 3,500 to 4,000 PSI for exterior flatwork. Ask your supplier what works in your climate and see the PSI guide.
How long before I can drive on a new driveway?
Foot traffic after a day or two, light vehicles after about seven days for many mixes, full strength at 28 days. Follow your supplier’s advice, especially in cold weather.
Sources
- QUIKRETE Concrete Mix No. 1101 data sheet (bag yields)
- PCA, Design and Control of Concrete Mixtures - Aggregates for Concrete (normal-weight concrete 140-150 lb/ft3)
- ACI 302.1R, Guide to Concrete Floor and Slab Construction (joint spacing 24-36 x thickness)
- Concrete Calculate - How Much Does Concrete Cost Per Yard Delivered? (2026)
- Concrete Network - concrete cost overview (2025 average about $180 per cubic yard)
- AllConcreteCalculator - concrete delivery cost and short-load fees (May 2026)
Estimate only. Results depend on the numbers you enter, ground conditions and your supplier. For structural work consult a licensed engineer and follow local codes. Brand names such as Quikrete and Sakrete are used only to cite published product data. This site is not affiliated with any brand.