Free calculators for site and project engineers

Site quantities, worked out right.

Concrete, rebar, programme dates and a BOQ that ties them together. Every result shows its working, so you can check it before it goes into a tender or a pour request.

Calculate concrete Open BOQ Builder

Example · Slab pourM20

10 × 6 m slab, 200 mm, +5% 12.60m³ 16.48 yd³ · 2 ready-mix trucks

Cement102 bags

Sand5.29 m³

Aggregate10.58 m³

Rebar Ø12 @ 150 c/c, one mat0.73 t

Shows the workingFormula and steps under every result.

Built for the UAELocal weekends, public holidays and AED pricing.

Feeds your BOQSend quantities straight into a priced bill.

No sign-upRuns in your browser. Nothing is uploaded.

Quantity calculators

Materials for each element

Live

Concrete Volume

Slabs, footings, beams and columns, with cement bags, sand, aggregate and water by mix grade.

Open calculator → Live

Rebar Weight

Bar schedule by diameter, length and count. Kilograms, tonnes and cost with lap allowance.

Open calculator →

Coming soon

Blockwork

Blocks per m², mortar and openings deduction for 100, 150 and 200 mm blocks.

Coming soon

Plaster and Tiles

Area, wastage, adhesive and grout quantities.

Coming soon

Paint

Litres by wall area, coats and coverage rate.

Coming soon

Excavation and Backfill

Cut, fill, bulking and compaction factors.

Project planning

Durations, progress and delay

Live

UAE Working Days

Working days between dates or a finish date from a duration, with UAE holidays and site weekends.

Open calculator →

Coming soon

Earned Value

CPI, SPI, EAC, ETC and VAC from planned, earned and actual cost.

Coming soon

Critical Path

Enter activities and links, get the critical path and a simple Gantt.

Coming soon

WBS Builder

Structure a project and export a P6-ready Excel sheet.

Cost and commercial

Price and track the work

Live

BOQ Builder

Sections, items, rates, VAT and grand total. Paste straight into Excel.

Open BOQ Builder →

Coming soon

Cost per m²

Budget estimate for villas, apartments and warehouses.

Coming soon

Retention and Advance

Retention held and advance payment recovery per invoice.

Engineering Stories

Collapses, accidents and lucky breaks

The bridges that danced, the tower that melted a car and the snack that invented the microwave. Real engineering history, and what it teaches us on site today.

All stories →

1940 · Bridge failure

Galloping Gertie

Drivers came from miles away to ride its waves. Then one November morning, the bridge started to twist.

Read the story →

2004–2010 · Record build

Burj Khalifa's night pours

Ice in the mix, pours at midnight and a world pumping record. Concrete engineering at 828 metres.

Read the story →

2013 · Design flaw

The Walkie-Scorchie

A businessman came back to his parked Jaguar and found it melting. The culprit was across the road.

Read the story →

1945 · Happy accident

The melted chocolate bar

A radar engineer reached into his pocket and found melted chocolate. Popcorn and an exploding egg came next.

Read the story →

2000 · Bridge failure

The Wobbly Bridge

London's millennium footbridge closed two days after opening. The problem was the people walking on it.

Read the story →

1173–2001 · Foundation failure

The Leaning Tower of Pisa

It began leaning before the third floor was finished. A war, a curve and some clever digging kept it standing.

Read the story →

Calculators made by people who work on site

EngCalcu is a free set of construction calculators for site engineers, quantity surveyors, planners and contractors. Each tool uses the formulas taught in engineering courses and used on real projects, such as the 1.54 dry volume factor for concrete and D²/162 for reinforcement weight, and shows every step so you can verify the figure.

The tools are tuned for projects in the UAE and the wider GCC, with the local weekend and public holiday calendar, metric units and AED pricing. They work equally well anywhere metric units are used.