Free construction calculators
Five free calculators answer the quantities you work out on site every day: how much steel, tile, flooring, concrete and blockwork a job needs. Each one gives you the count in seconds — free forever, no signup, no ads, metric or imperial.
The five calculators
Steel Weight Calculator
Weight of steel sheet and plate, and rebar by the bar — in kilos or pounds.
Open the calculator → Tiling & FlooringTile & Grout Calculator
Tiles, grout, adhesive bags and backer boards for any room, with waste.
Open the calculator → Wood & Vinyl FlooringFlooring Calculator
Planks and boxes for wood, laminate and vinyl — or the roll length for carpet.
Open the calculator → Masonry & PlasterConcrete Calculator
Volume and premix bags for slabs and footings, plus rebar, mesh, gravel and formwork.
Open the calculator → Masonry & PlasterBlock & Brick Calculator
GCC concrete blocks with mortar, or classic brick walls — count and mortar bags.
Open the calculator →How the free tools work
Pick a calculator, type the measurements in metres or feet, and read the quantities — tiles, bags, bars, blocks — with waste added where the trade adds it. Every result ends with one move: turn the quantities into a quote in InstaJack and send it on WhatsApp.
Which calculator do I need?
Weighing steel, plate or rebar?
The steel weight calculator weighs sheet and plate from their size and the metal’s density, and rebar by the standard weight of each bar size — in kilos or pounds.
Steel Weight Calculator →Counting tiles, grout or adhesive?
The tile & grout calculator counts tiles with waste, the grout the joints will drink, adhesive bags and backer boards for any room.
Tile & Grout Calculator →Ordering planks, boxes or carpet?
The flooring calculator counts planks and boxes for wood, laminate and vinyl, the roll length for carpet, and underlayment rolls.
Flooring Calculator →Pouring a slab or a footing?
The concrete calculator gives the volume and premix bags, plus the rebar grid, mesh, gravel bed, vapour barrier and formwork that go with the pour.
Concrete Calculator →Building a block or brick wall?
The block & brick calculator counts GCC concrete blocks or standard bricks for a wall, with the mortar bags they need.
Block & Brick Calculator →Why are these calculators free?
Because they are the front door to InstaJack. The calculators count materials; InstaJack turns the same quantities into a priced quote from your own price book and sends it on WhatsApp. Use the tools as often as you like — whether or not you ever open the app, they stay free, with no email form and no ads.
Questions about the free tools
Are these calculators really free?+
Yes — free forever, with no signup, no ads and no email form. They are the front door to InstaJack: use them as often as you like, whether or not you ever open the app.
Do the numbers carry into InstaJack automatically?+
Not yet. Today you read the quantities here and type them into your quote, like any line from your price book. The calculators stay free on this site either way.
Why do the calculators show quantities but no prices?+
Because prices are yours. Material rates change by city, supplier and week, so a honest calculator counts materials and leaves pricing to your own price book in InstaJack.
Do the calculators work in metric and imperial?+
Yes — every calculator carries a metric/imperial switch and opens in metric. Sizes, bag yields and rates follow the system you pick, so a Gulf crew in metres and a US crew in feet get the same honest sums.
Who are these calculators for?+
Small firms and tradies — tilers, masons, steel fixers, flooring crews — who work out material quantities on site, on a phone. The pages are built for a phone screen first: big fields, live results, no account.
Do the calculators give prices as well as quantities?+
No — quantities only, deliberately. Material prices change by city, supplier and week, so a honest calculator counts the materials and leaves pricing to your own price book in InstaJack, where your rates live.