How much concrete do I need for a slab?

To calculate concrete needed for a slab, multiply length × width × thickness. For a 10ft × 10ft × 4-inch slab, you need approximately 1.23 cubic yards. Our calculator automatically includes the 10% waste factor.

How many bags of concrete do I need calculator?

The number of bags depends on your slab size and bag weight. For example, an 80lb bag covers about 0.44 cubic yards. A 10×10×4 inch slab would need approximately 3 bags of 80lb concrete mix.

How to calculate cubic yards of concrete?

Convert all measurements to feet first. Then use: Cubic Yards = (Length × Width × Thickness in feet) ÷ 27. For inches, divide thickness by 12 to convert to feet before calculating.

What is the concrete calculator formula?

Basic formula: Volume = L × W × T. For imperial units: Cubic Yards = (Length ft × Width ft × Thickness in) ÷ 324. For metric: Cubic Meters = (Length m × Width m × Thickness cm) ÷ 100.

How much does concrete cost per yard?

Bagged concrete typically costs $6-8 per 80lb bag, covering about 0.44 cubic yards each. Ready-mix concrete costs $100-150 per cubic yard. Our calculator compares different bag sizes for the best value.

How to calculate concrete bags needed?

First calculate your volume in cubic yards, then divide by the coverage per bag. An 80lb bag covers 0.44 cu yd, 60lb covers 0.33 cu yd, and 40lb covers 0.22 cu yd. Always round up and add 10% extra.

How to calculate concrete for a slab?

Measure length, width, and thickness of your slab. Convert to consistent units (all feet or all meters). Multiply these three dimensions to get volume. Add 10% waste factor for material ordering.

How much concrete will I need calculator?

Our free calculator provides instant results for any rectangular slab. Simply enter your dimensions, and it calculates volume, bags needed, and total cost automatically. Works for both imperial and metric measurements.

How do you calculate yards of concrete?

To calculate concrete yards: (Length ft × Width ft × Depth ft) ÷ 27 = Cubic Yards. For depth in inches, convert to feet first by dividing by 12. Example: 12ft × 12ft × 4in = 12 × 12 × 0.33 ÷ 27 = 1.78 cubic yards.

What thickness should my concrete slab be?

Standard thicknesses: Sidewalks - 4 inches, Driveways - 4-6 inches, Garage floors - 4-6 inches, Basement floors - 4-8 inches. Thicker slabs provide more durability but require more concrete.

Should I include a waste factor?

Yes, always include 10-15% waste factor when ordering concrete. This accounts for spillage, over-excavation, and measurement variations. Our calculator automatically includes 10% waste factor in all calculations.

Can I use this for non-rectangular footings?

For irregular shapes, break them into rectangular sections and calculate each separately, then add the volumes together. For circular slabs, use our Circular Calculator tool available in the sidebar menu.

How accurate is this calculator for cost estimation?

Our calculator provides highly accurate cost estimates based on current market prices. The calculator uses real-time pricing data and factors in regional cost variations to deliver precise cost calculations for your concrete projects.

Can this calculator help me save money on concrete costs?

Yes! Our smart calculator compares different bag sizes and shows cost-per-unit breakdowns to help you identify the most cost-effective purchasing options. The calculator also prevents over-ordering by providing accurate calculations.

What factors affect concrete cost in the calculator?

The calculator considers multiple cost factors including bag sizes, regional pricing, quantity discounts, and delivery costs. Geographic location significantly impacts concrete cost, and our calculator adjusts pricing automatically.

How does the calculator compare costs between bag sizes?

Our calculator analyzes cost-per-cubic-yard for each bag size option, showing you the total project cost breakdown. The calculator highlights the most economical choice by comparing unit costs.

Is this calculator suitable for commercial cost estimating?

While our calculator provides professional-grade calculations suitable for many commercial projects, larger commercial cost estimates may require additional factors like labor costs and equipment costs.

Concrete Footing Calculator

Footing Concrete Calculator

Calculate concrete volume, bags needed, and total cost for foundation footing projects. Supports multiple footings calculation

Length (ft)

Width (ft)

Thickness (in)

Number of Footings

Enter total number of footings needed

Per Footing Volume

0 cu yd

Total Volume Needed

0 cu yd

3D Shape Preview

Why Choose Our Concrete Footing Calculator?

Professional concrete footing calculator for foundation footers, wall footings, column pads, and building foundations with accurate cost estimates.

Footing & Foundation Calculator

Calculate concrete for wall footings, column footings, spread footers, and foundation pads. Supports rectangular and square footing dimensions.

Foundation Concrete Volume

Accurate foundation concrete calculator for continuous footings, isolated pads, and strip foundations with precise volume formulas.

Footing Cost Calculator

Concrete footing cost calculator with material estimates. Compare ready-mix vs bagged concrete prices for your foundation project budget.

Footer Size Calculator

Calculate footer dimensions and concrete volume for building codes. Wall footer calculator for 8", 10", 12" wide foundations with depth requirements.

Dual Unit System

Calculate in feet/inches or meters/centimeters. Instant conversion for foundation concrete footings and international building projects.

Free & Easy to Use

No registration required. Free concrete footing calculator for contractors, builders, and DIY foundation projects with instant results.

How to Calculate Concrete for Footings & Foundations

Follow these steps to calculate concrete for foundation footings, wall footers, and column pads with accurate volume estimates.

Measure Your Footing Dimensions

Measure the length, width, and depth of your concrete footing. For wall footings, measure along the entire wall length. For column footings, measure the pad dimensions.

Tip: Standard wall footing width is typically 2x the wall thickness. Minimum depth is usually 12 inches below frost line.

Enter Footing Measurements

Input your footing dimensions into the calculator. Choose between imperial (feet/inches) or metric (meters/centimeters) for foundation calculations.

Note: Common footing sizes: 8" wall = 16" wide footing, 10" wall = 20" wide footing, 12" wall = 24" wide footing.

Review Concrete Volume & Cost

See total cubic yards needed for your footing. Calculator shows bags required or ready-mix volume with cost estimates for your foundation project.

Important: Foundation concrete costs $100-150 per cubic yard for ready-mix, or $6-8 per 80lb bag.

Compare Ready-Mix vs Bags

Compare ready-mix concrete delivery vs bagged concrete for your footing project. Calculator helps find the most cost-effective foundation solution.

Pro Tip: Ready-mix is more economical for footings over 1 cubic yard. Bags work best for small footing repairs.

Footing Concrete Formula

Footing Volume Formula:

Volume = Length × Width × Depth

Imperial Footing Calculation:


                        Volume (cu yd) = (Length ft × Width ft × Depth in) ÷ 324

Metric Foundation Calculation:


                        Volume (cu m) = Length m × Width m × Depth cm ÷ 100

Standard Footing Sizes:

• 8" wall: 16" wide × 8" deep footing
• 10" wall: 20" wide × 10" deep footing
• 12" wall: 24" wide × 12" deep footing
• Column pad: 24"×24" × 12" deep minimum

Frequently Asked Questions About Footing Calculators

Common questions about calculating concrete for footings, foundations, footers, volume requirements, and foundation cost estimation.

How to calculate concrete footings?

To calculate concrete for footings, multiply length × width × depth. For a 20ft long × 16" wide × 8" deep wall footing: (20 × 1.33 × 0.67) ÷ 27 = 0.66 cubic yards. Our concrete footing calculator automatically handles these conversions and includes waste factor for accurate foundation planning.

How much concrete for footings?

Concrete volume for footings depends on dimensions. A typical 8" wall needs a 16" wide × 8" deep footing. For 30 linear feet: (30 × 1.33 × 0.67) ÷ 27 = 0.99 cubic yards. Use our footing calculator to determine exact amounts for your foundation project dimensions.

What is a concrete footing calculator?

A concrete footing calculator computes the volume of concrete needed for foundation footers and footings. It calculates cubic yards or bags required based on footing length, width, and depth. Essential tool for estimating foundation concrete costs and material planning for building projects.

How to calculate concrete for foundation?

Foundation concrete calculation: Volume = Length × Width × Depth ÷ 27 (for cubic yards). For imperial: (L ft × W in × D in) ÷ 324. For metric: (L m × W cm × D cm) ÷ 100 for cubic meters. Our foundation calculator uses precise formulas for accurate footing volume estimates.

What is the difference between footing and footer?

Footing and footer are the same thing - the concrete base that distributes building loads to soil. "Footing" is more common in construction terminology. Both refer to the foundation element below walls or columns. Wall footings support walls, column footings (pads) support posts.

How much does a concrete footing cost?

Concrete footing costs $100-150 per cubic yard for ready-mix, or $6-8 per 80lb bag. A typical house footing (3-4 cubic yards) costs $300-600. Our concrete footing cost calculator helps estimate total materials and compares ready-mix vs bagged concrete pricing for your foundation budget.

How deep should concrete footings be?

Concrete footing depth should be minimum 12 inches below frost line (varies by region: 12-48 inches). Standard depth is 8-12 inches for most residential footings. Footing depth must extend below undisturbed soil. Check local building codes for specific frost depth and foundation requirements in your area.

What size footing do I need?

Footing size depends on wall thickness and soil bearing capacity. General rule: footing width = 2× wall thickness. For 8" wall use 16" wide footing, 10" wall needs 20" wide, 12" wall requires 24" wide footing. Depth typically equals footing width. Column footings need larger pads based on load calculations.

How to calculate footing size?

Calculate footing size based on wall thickness and soil capacity. Formula: Footing Width = Wall Thickness × 2. Depth = Footing Width (typically). For 10" concrete block wall: 20" wide × 20" deep footing. Always verify with local building codes and soil engineer for proper foundation sizing.

How much concrete for foundation walls?

Foundation wall concrete: Volume = Length × Height × Thickness ÷ 27. For 40ft long × 8ft high × 8" thick wall: (40 × 8 × 0.67) ÷ 27 = 7.95 cubic yards. Add footing volume separately. Our foundation calculator computes both footings and walls for complete basement estimates.

What is the formula for footing concrete?

Footing concrete formula: Volume = Length × Width × Depth. For cubic yards: (L ft × W in × D in) ÷ 324 = cu yd. Example: 30ft long × 16" wide × 8" deep = (30 × 16 × 8) ÷ 324 = 11.85 cu yd. Our calculator applies this formula automatically for accurate footing volume.

How to calculate footer volume?

Footer volume calculation: Convert all measurements to same unit (feet), then multiply length × width × depth ÷ 27 for cubic yards. For stepped footings, calculate each section separately and add volumes. Always add 10% waste factor when ordering concrete for footers and foundation work.

Do I need rebar in footings?

Yes, most building codes require rebar in concrete footings for reinforcement. Typical requirement: #4 rebar (1/2") continuous along footing length, placed 3" from bottom. Some codes require double rebar for wider footings. Always check local codes for specific rebar requirements in foundation footings.

What is the minimum footing depth?

Minimum footing depth is 12 inches below undisturbed soil and below frost line. Frost depth varies by climate: southern US 12-18", northern US 36-48". Footing bottom must rest on stable, undisturbed soil. Never pour footings on fill dirt or frozen ground. Verify local code requirements.

How to calculate concrete footing cost?

Calculate footing cost by multiplying cubic yards × price per yard. Ready-mix: $100-150/yard. For 2 cubic yards: $200-300. Add rebar ($0.50/ft), excavation ($2-4/sq ft), and labor ($4-8/sq ft). Our concrete footing cost calculator provides material estimates with ready-mix vs bagged concrete comparison for budget planning.

Concrete Calculation Guide

Essential knowledge for accurate concrete calculations, measurement tips, and project planning guidelines.

Footing Measurement

• Measure footing length along wall centerline
• Footing width = 2× wall thickness minimum
• Standard footing depth: 8" to 12"
• Account for stepped footings on slopes
• Measure below frost line depth
• Add excavation overdig (4-6" each side)

Foundation Specifications

Standard Footing Sizes:

• 8" wall: 16"W × 8"D footing
• 10" wall: 20"W × 10"D footing
• 12" wall: 24"W × 12"D footing

Code Requirements:

• Minimum depth: 12" below grade
• Below frost line: 12"-48" varies
• Rebar: #4 continuous required

Cost Estimation

Ready-Mix Concrete:

$100-150 per cubic yard delivered

Rebar & Materials:

$0.50-0.75 per linear foot

Labor (if hiring):

$4-8 per square foot installed

Project Planning

• Order 10-15% extra concrete
• Schedule delivery for early morning
• Have tools ready before mixing
• Check weather forecast (no rain)
• Prepare sub-base and forms first
• Plan for immediate use of mixed concrete

Cost Considerations

• Bagged: $6-8 per 80lb bag
• Ready-mix: $100-150 per cubic yard
• Delivery fees: $50-100 typical
• Minimum orders may apply
• Weekend/overtime rates higher
• Compare total project cost, not just per-unit

Quality Tips

• Use proper water-to-cement ratio
• Avoid adding excess water
• Consolidate concrete to remove air
• Level and smooth surface properly
• Allow adequate curing time
• Protect from temperature extremes

Quick Reference: Common Footing & Foundation Sizes

Common footing sizes showing volume requirements and costs for different wall thicknesses
Footing Type	Size (W×D)	Per 10 ft (cu yd)	Estimated Cost
8" Wall Footing	16" × 8"	0.33 cu yd	$35-50
10" Wall Footing	20" × 10"	0.51 cu yd	$55-75
12" Wall Footing	24" × 12"	0.74 cu yd	$75-110
Column Pad 24×24	24" × 12"	0.22 cu yd	$25-35
Column Pad 30×30	30" × 12"	0.35 cu yd	$35-50

* Costs based on ready-mix concrete at $100-150/cu yd. Add rebar and labor for total project cost.