Construction Calculators

Free online tools to estimate materials for any construction or renovation project. Calculators are grouped into six categories: Excavation & Earthworks, Concrete & Masonry, Roofing & Structure, Surfaces & Finishes, Landscaping & Site Work, and Utilities & Converters. Search by name or browse by category to find the right calculator, then follow our in-depth guides to understand the math behind each estimate.

Calculators for excavation planning, soil management, hauling logistics, and OSHA trench safety compliance. Covers trench volume, foundation dig, swell and shrink conversion, truckload estimation, and cost breakdowns.

Excavation Volume Calculator

earthworks

Estimate dig volumes for trenches, foundations, and site clearance, with soil swell factors to plan spoil removal and haulage.

Trench Volume Calculator

earthworks

Calculate trench excavation volume for utilities, footings, and drainage with rectangular or trapezoidal cross-sections. Includes soil swell factors and OSHA depth warnings.

Topsoil Removal Calculator

earthworks

Estimate topsoil stripping volume, weight, and truckloads from area and strip depth for site preparation and grading projects.

Soil Swell & Shrink Calculator

earthworks

Convert between bank, loose, and compacted soil volumes instantly. Enter any one volume state to see all three with soil-specific swell and shrink factors.

Dump Truck Load Calculator

earthworks

Calculate how many dump truck trips you need with both volume and weight limit checks. Compares volume-limited and weight-limited trip counts.

Foundation Excavation Calculator

earthworks

Calculate foundation dig volume for slab, crawlspace, or basement with working room allowance and optional strip footing volume.

Backfill Calculator

earthworks

Calculate backfill material needed after pipe installation with compaction factor and pipe displacement.

Cut and Fill Calculator

earthworks

Calculate cut and fill balance with swell and shrink factors for earthwork grading.

Spoil Pile Calculator

earthworks

Calculate spoil pile footprint, height, and staging area from excavated volume.

Excavation Cost Calculator

earthworks

Estimate excavation costs with itemized breakdown: dig, hauling, disposal, labor, equipment.

OSHA Trench Sloping Calculator

earthworks

Plan trench slope setback and top width from OSHA Appendix B maximum allowable slope tables by soil type.

Calculate exact quantities for concrete pours, block walls, mortar, and reinforcement. From slabs and footings to retaining walls and thinset adhesive, these tools handle the volume math so you order the right amount.

Accurate material counts for roofing, wall framing, insulation, and exterior cladding. From measuring roof pitch to counting shingles, calculating gutter runs, and estimating insulation rolls for walls and ceilings.

Figure out what you need for paint, tile, flooring, drywall, and decking. These tools account for waste factors, pattern layouts, coverage rates, and finish levels so you buy the right amount the first time.

Paint Coverage Calculator

paint

Calculate how many liters of paint you need for walls, ceilings, and trim using room dimensions, coat count, and standard coverage rates.

Tile Calculator

flooring

Work out how many tiles to order for floors and walls, with waste factors adjusted for grid, diagonal, and herringbone patterns.

Flooring Calculator

flooring

Estimate flooring materials — laminate, vinyl, or hardwood — for any room size, including waste allowance for cuts and fitting.

Drywall Calculator

interior

Calculate the number of drywall sheets for walls and ceilings, with deductions for doors, windows, and standard sheet sizes.

Self-Leveling Compound Calculator

flooring

Calculate bags of self-leveling compound for floor preparation based on area, pour depth, and product coverage rate.

Decking Calculator

outdoor

Calculate deck boards needed for your outdoor deck, with waste factors adjusted for board direction, joist spacing, and deck shape.

Primer Calculator

paint

Calculate primer gallons needed for drywall, wood, masonry, or previously painted surfaces with coverage rates by surface type.

Room Paint Calculator

paint

Calculate paint needed for a room by entering length, width, and height. Wall area auto-computed with L/gal toggle — no door or window counting required.

Exterior Paint Calculator

paint

Estimate exterior paint quantity with a surface type selector for brick, wood, stucco, and render. Coverage rates adjusted per surface with L/gal toggle.

Paint Cost Calculator

paint

Estimate total paint cost from quantity and price per liter or gallon. Includes coats, waste factor, and an itemized cost breakdown table.

Joint Compound Calculator

interior

Calculate joint compound, paper tape, and drywall screws by sheet count and finish level per Gypsum Association standards.

Drywall Paint Calculator

paint

Calculate paint quantity for drywall with surface condition selector — unprimed new drywall requires more paint due to absorption. Includes L/gal toggle.

Trim Paint Calculator

paint

Calculate trim and baseboard paint quantity from linear metres. Converts trim length to effective area using trim type width — baseboard, door casing, or window trim.

Fence & Deck Stain Calculator

paint

Calculate fence and deck stain quantity with wood type selector. Species-specific coverage rates for rough cedar (4 m²/L), smooth pine (8 m²/L), and pressure-treated pine (6 m²/L).

Spray Paint Coverage Calculator

paint

Calculate spray paint quantity with sprayer type selector. Airless and HVLP modes adjust for transfer efficiency. Aerosol mode outputs can count instead of volume.

Estimate materials for gravel driveways, garden beds, mulch coverage, and paving projects. Convert between volume and weight for bulk materials delivered by the truckload.

Gravel Calculator

gravel

Calculate gravel volume in cubic meters and weight in tonnes for driveways, paths, and drainage, with density values by material type.

Paver Calculator

landscaping

Estimate paver quantities for patios, driveways, and walkways, including waste allowance for cutting patterns and edge trimming.

Topsoil & Mulch Calculator

landscaping

Estimate topsoil, mulch, or bark quantities by area and desired depth for garden beds, lawn prep, and landscaping projects.

Gravel Weight Calculator

gravel

Calculate gravel weight from volume using material-specific bulk density. Select aggregate type to convert m³ to kg or lbs instantly.

Gravel Cost Calculator

gravel

Estimate total gravel cost from volume with waste factor. Price by cubic meter or tonne with an itemized cost breakdown table.

Gravel Truckloads Calculator

gravel

Calculate how many dump truck trips you need to deliver gravel. Select truck payload size — trip count rounds up to whole trips.

Driveway Gravel Calculator

gravel

Calculate gravel quantity for driveways, paths, patio bases, and drainage layers. Depth auto-fills from application type selection.

Crushed Stone Calculator

gravel

Calculate crushed stone volume and weight for base layers, driveways, drainage, and landscaping. Choose limestone, granite, or recycled concrete (RCA) for accurate density calculations.

Pea Gravel Calculator

gravel

Calculate how many bags of pea gravel you need for paths, garden beds, and decorative areas. Choose 25kg or 50kg bags — bag count rounds up to the nearest whole bag.

Paver Base Calculator

gravel

Calculate two-layer paver sub-base: drainage rock (1.45 t/m³) and compacted road base (2.0 t/m³, 1.15× compaction factor). Layer-by-layer breakdown plus combined totals.

French Drain Calculator

gravel

Calculate drainage gravel for French drain trenches. Accounts for pipe displacement using π × (OD/2)² × length formula. Select 100mm, 150mm, or 200mm pipe.

Road Base Calculator

gravel

Calculate road base (DGB/crusher run) order quantity from compacted depth. Compaction factor 1.30–1.35× works out loose volume needed. Density 2.0 t/m³.

Convert between metric and imperial units or translate volume to weight for common construction materials. Handy reference tools that support every other calculator on this site.

How to Use These Calculators

Step 1

Measure Your Space

Take accurate length, width, and depth measurements of the area you plan to cover, fill, or build. Double-check corners and irregular sections.

Step 2

Enter Your Numbers

Choose the calculator that matches your project and enter your measurements. Each tool adjusts for waste factors, coverage rates, and packaging sizes automatically.

Step 3

Order with Confidence

Get an instant material list with quantities, bag counts, or board counts. Most estimates include a waste buffer so you don't run short mid-project.

Why Accurate Material Estimation Matters

Over-ordering construction materials wastes money and creates disposal headaches. Under-ordering means project delays, extra delivery fees, and the risk of mismatched material batches. Our calculators use industry-standard formulas and waste factors so your estimates land in the sweet spot: enough material to finish the job with a small safety margin, without buying more than you need.

Every calculator on this page is free, works on any device, and requires no sign-up. Enter your measurements, get your result, and head to the store. For a deeper understanding of the formulas and trade tips behind each tool, check the complete estimation guide.

In-Depth Guides

Go beyond the numbers. Each guide explains the formulas, waste factors, and real-world tips behind every calculator in its category.