Construction tools that run in your browser.
Measure once, estimate in seconds. Work out an area below, then send the number straight into the calculator that turns it into materials.
- Metric and imperial
- Nothing leaves your device
- Free, no account needed
Work out an area, then estimate the materials
20.00m²
215.28 ft²23.92 yd²
Free
Every calculator on Siteometry is free and unlimited. No trial, no paywall, no upsell at the result.
Nothing leaves your device
Every calculation runs in your browser. Your dimensions, prices and projects stay on your device and are never uploaded.
Works offline
Install Siteometry as an app and the calculators keep working on site, with no signal and no data.
No login, nothing in the way
Open a tool and start typing. No account, no email, no cookie wall between you and the number.
Start here
The calculators most jobs begin with — concrete volume and bags, paint coverage, tile counts, drywall sheets, roof squares, aggregate tonnage, excavation and area.
Bar Bending Schedule
Cut lengths, bend allowances and total rebar weight — instantly.
Paint Coverage & Cost Calculator
Paint, primer, the cheapest tins to buy and the cost — per room.
Tile & Flooring Calculator
Tiles, boxes to buy, grout and adhesive — with pattern waste built in.
Concrete Volume & Bag Calculator
Volume, bags to buy and the cost — slabs, footings, columns and stairs.
Roofing Calculator — Pitch, Area & Materials
Roof pitch, sloped area, shingles, metal or tile, accessories and cost.
Gravel, Sand & Aggregate Calculator
Order weight, volume, bags and cost for gravel, sand or topsoil — multiple zones, compaction and waste accounted for separately.
Paver & Patio Calculator
Pavers, base gravel, bedding sand and polymeric sand for a patio or walkway — with pattern waste, dig depth, cost and a live layout diagram.
Drywall & Plasterboard Calculator
How many sheets, plus joint compound, tape and screws for walls and ceilings — deduct openings, pick a sheet size, metric or imperial.
Excavation & Trench Volume Calculator
Cut volume, soil swell, spoil weight, truckloads and cost for pads, trenches and pier holes — multiple zones, metric or imperial.
Square Footage Calculator — Area of Any Room or Shape
Free square footage calculator: measure the area of rectangles, L-shaped rooms, circles and triangles — or enter a known area — then convert to m², yd², acres or hectares, add waste and price, all in your browser.
Browse by trade
Nine categories cover the whole catalog: concrete and masonry, steel and rebar, framing and carpentry, decorating and interiors, roofing and siding, landscaping and garden, hardscaping and paving, earthworks and excavation, and area and unit conversions. Each one is a guide as much as a list.
Concrete & Masonry
Volume, bags, mix ratios, bricks, blocks and mortar — priced and ordered right.
- Concrete Volume & Bag Calculator
- Brick & Block Calculator
- Concrete Mix Ratio Calculator
Steel & Rebar
Bar bending schedules, cutting lengths, lap lengths and rebar weight by tonne.
- Steel Quantity Estimator — Steel per m³ of Concrete
- Bar Bending Schedule
- Cutting Length Calculator — Stirrups, Rings & Bent Bars
Framing & Carpentry
Studs, plates, stairs, board feet, decks and fences — timber counted properly.
- Deck & Patio Cost Calculator
- Deck Railing & Baluster Spacing Calculator
- Deck Joist & Beam Span Calculator
Decorating & Interiors
Paint, tile, flooring, wallpaper, carpet, drywall, plaster, insulation and BTU sizing.
- Paint Coverage & Cost Calculator
- Tile & Flooring Calculator
- Flooring Calculator — Laminate, Vinyl Plank & Hardwood
Roofing & Siding
Roof pitch and area, shingles and bundles, siding squares, trim and insulation.
- Roofing Calculator — Pitch, Area & Materials
- Roof Truss Calculator — How Many Trusses & Cost
- Siding Calculator — Squares, Panels, Boxes & Trim
Landscaping & Garden
Mulch, topsoil, raised-bed mixes, grass seed, sod, decks and fences.
- Pool Volume Calculator
- Mulch Calculator
- Topsoil & Raised-Bed Soil Calculator
Hardscaping & Paving
Pavers, patio bases, gravel and aggregate, asphalt driveways and retaining walls.
- Gravel, Sand & Aggregate Calculator
- Paver & Patio Calculator
- Asphalt Driveway & Paving Calculator
Earthworks & Excavation
Trench and pad volumes, cut and fill, soil swell, truckloads and cubic yards.
- Excavation & Trench Volume Calculator
- French Drain & Drainage Calculator
- Cubic Yards / Volume Calculator
Area & Conversions
Square footage, cubic yards, board feet, tank capacity and land-area units.
- Water Tank Capacity Calculator
- Land Area Unit Converter — Bigha, Katha, Gunta & Acre
- Square Footage Calculator — Area of Any Room or Shape
Electrical
Voltage drop, wire and cable sizing, and conductor selection for copper or aluminium.
- Voltage Drop & Wire Size Calculator
- Electrical Load & Service Size Calculator (NEC 2023)
- Wire Size Calculator — NEC Ampacity & Voltage Drop
Looking for something specific?
The complete index lists all 63 calculators A–Z with a live search — by name, by material, or by the unit you have to order in.
From the site notebook
Guides to the maths behind the tools — bar bending schedules, lap and development lengths, concrete mixes, and the rules of thumb worth checking before you order.
How to Estimate Paint Quantity for a Room
A practical method for working out how much paint a job needs, covering paintable area, openings, coverage rates, coats, primer, waste allowance, and turning litres into tins.
How to Calculate Concrete Volume for Slabs, Footings and Foundations
A practical guide to working out concrete volume for slabs, strip and pad footings, and foundation walls, with formulas, unit conversions, waste allowance, and bag estimates.
How to Prepare a Bar Bending Schedule
A practical walkthrough for turning reinforcement drawings into a clear bar bending schedule with marks, shape codes, diameters, spacing, cutting lengths, weights, and checks.
Questions, answered
What Siteometry is, how the numbers are worked out, and what happens to what you type.
Are the calculators really free?
Yes. Every calculator is free and unlimited, with no account and no paywall. There is no premium tier holding the useful result back.
Does anything I type get uploaded?
No. Every calculation runs in your browser, so your dimensions, prices and project details never leave your device — and the projects you save are stored locally in the browser.
Do the tools work in metric and imperial?
Yes. Nearly every calculator has a metric/imperial switch and converts what you have already typed when you flip it. Work in metres and millimetres or in feet and inches, and read results in m², ft², cubic yards, tonnes, bags, boxes or sheets.
Can I use Siteometry on site with no signal?
Yes. Siteometry is an installable progressive web app: add it to your home screen and the calculators keep working offline, which is exactly the point on a site with no coverage.
How accurate are the estimates?
The maths is exact for the geometry and the standards each tool implements, and every tool shows its assumptions — waste allowance, coverage rate, bag yield, bar bending code. But an estimate is only as good as its inputs and its allowances, so treat the output as a well-founded quantity take-off to check against your supplier's data sheet, not as a replacement for one.
Which calculator should I start with?
If you know the job, go straight to the tool — paint, tile, flooring, concrete, drywall, roofing, fence or gravel. If you only know the room, start with the area estimate at the top of this page and then follow one of the material links under the result.