How much ready-mix concrete should I order?
Ready-mix is usually ordered in cubic yards. Calculate project volume, add a practical waste buffer, then discuss rounding, minimum order size, and delivery timing with the supplier.
Ready-mix order planning
Suppliers may have minimum loads, short-load fees, delivery windows, truck access limits, and rounding rules. The calculator gives a quantity estimate, not a supplier quote.
Before the truck arrives
Forms, base prep, reinforcement, access, tools, finishers, and weather timing should be ready before delivery. Concrete quantity does not solve placement logistics.
Concrete bag planning table
Uses common planning yields: 0.60 cu ft per 80 lb bag and 0.45 cu ft per 60 lb bag. Verify the product label.
| Concrete volume | Cubic feet | 80 lb bags | 60 lb bags |
|---|---|---|---|
| 0.25 cu yd | 6.75 cu ft | 12 bags | 15 bags |
| 0.50 cu yd | 13.5 cu ft | 23 bags | 30 bags |
| 1.00 cu yd | 27 cu ft | 45 bags | 60 bags |
| 2.00 cu yd | 54 cu ft | 90 bags | 120 bags |
Before you calculate
- Use the yield printed on the bag you plan to buy, because 40 lb, 50 lb, 60 lb, and 80 lb products can differ.
- Measure project area and thickness before converting the volume into bags.
- Keep waste visible for over-excavation, uneven base, mixing loss, and final top-off.
Common mistakes
- Assuming every bag yields the same cubic feet.
- Buying by bag weight without checking volume yield.
- Forgetting that the final answer must round up to whole bags.
Formula
bags = ceil((area * (thickness / 12) * (1 + wastePercent / 100)) / yieldPerBag)
Assumptions
- Use the bag yield printed on the product label.
- Thickness is entered in inches.
- Bagged ready-mix is practical for small pours; larger jobs may be better as delivered ready-mix.
Example
Estimated ready-mix bags needed: 49 bags
How to calculate ready mix bags
- Measure the ready mix bag project area or volume that needs bagged material.
- Enter thickness, depth, coverage, or yield per bag from the exact product label.
- Keep waste visible for cuts, uneven base, mixing loss, spreading loss, and final top-off.
- Divide adjusted demand by the product yield and round up to whole bags.
- Confirm product instructions, water or installation requirements, delivery units, and site conditions before buying.
Before you buy materials
- Round up to full bags and compare the total bag count with ready-mix if the quantity gets large.
- Check the product label for yield, water instructions, working time, and intended use.
FAQ
How many bags do I need for ready mix bag?
Use area, depth or thickness, product yield per bag, and waste, then round up to the buying unit when the result is sold as whole items. In the default example, the result is 49 bags.
How is ready-mix concrete measured?
Ready-mix concrete is commonly ordered by cubic yard. One cubic yard equals 27 cubic feet.
Should I round up my ready-mix order?
Usually yes. Ask the supplier how they handle order increments, minimums, and short-load fees.
Does this include delivery cost?
No. It estimates quantity only. Delivery, short-load, pump, and scheduling fees vary by supplier.
Can I use bags instead of ready-mix?
For small pours, maybe. For larger volumes, compare the bag count, labor, mixing time, and ready-mix supplier minimums.
Related calculators
This calculator is for planning estimates only. Verify final quantities with product labels, project conditions, and a qualified professional when accuracy matters.