Engineering & Trades
Electrical, structural, mechanical, welding, plumbing, HVAC, concrete, surveying, HSE, and project tools for engineers and tradespeople.
70 calculators
Rigging weight calculator
Calculate the weight of any structural section, plate, or solid shape across 34 materials and 14 cross-section types. Includes multi-item load builder and SWL guidance.
Floor load bearing calculator
Calculate the load per unit area for a distributed load on a floor, slab, or platform.
Simply supported beam deflection
Calculate mid-span deflection of a simply supported beam under a central point load.
Sling Tension Calculator
Calculate tension in each leg of a 2-leg or 4-leg chain/wire sling given load and included angle.
Crane Outrigger Load
Estimate maximum ground bearing load under a crane outrigger from rated capacity and radius.
Shackle WLL Selector
Select the minimum rated shackle size for a given load, including dynamic factor and angle effects.
Scaffolding Bay Load
Check platform board load rating and calculate total bay load from workers, materials, and tool loads.
Cable Size Selector
Select the correct cable cross-section or AWG size for any load based on current-carrying capacity and voltage drop.
Voltage Drop Calculator
Calculate voltage drop along a cable run and check compliance with NEC, AS/NZS 3008, or BS 7671 limits.
Circuit Breaker Sizing
Determine the minimum circuit breaker or fuse rating for any electrical load type.
Power Factor Correction
Calculate the capacitor bank size (kVAR) needed to correct power factor to a target value.
Motor Starter Sizing
Size the contactors, overload relay, and branch circuit for a three-phase induction motor.
Generator Sizing
Size a standby or prime generator (kVA) for a building or industrial load list.
Conduit Fill Calculator
Check that cables fit within conduit fill limits per NEC or AS/NZS 3000 Wiring Rules.
LED Lighting Upgrade Savings
Calculate energy and cost savings from replacing fluorescent or halogen fittings with LED.
Solar PV String Sizing
Size solar PV string configurations against inverter MPPT voltage and current windows.
Earth Fault Loop Impedance
Calculate maximum allowable Zs and verify that fault current will trip the protective device within the required time.
Steel Beam Selector (UB/UC)
Select the minimum Universal Beam or Column section to carry a given simply-supported load.
Column Buckling (Euler)
Calculate the critical buckling load for a slender steel or timber column using Euler's formula.
Footing Bearing Pressure
Calculate actual bearing pressure under an isolated pad footing and compare to allowable soil bearing capacity.
Wind Load (Simplified)
Estimate wind pressure and base shear on a rectangular building using codified simplified methods.
Retaining Wall Stability
Check overturning and sliding stability of a gravity retaining wall using Rankine active earth pressure.
Bolt Group Shear (Elastic Method)
Calculate maximum shear in an eccentrically loaded bolt group using the elastic method.
Snow Load (Roof)
Estimate roof snow load from site ground snow load, roof slope, and exposure per AS/NZS 1170.3 or ASCE 7.
RC Slab Thickness (Span-Depth Ratio)
Estimate minimum reinforced concrete slab thickness from span-to-depth ratio rules in AS 3600 or ACI 318.
Concrete Mix Design (Nominal)
Estimate constituent quantities for a nominal concrete mix by mass and volume per m³.
Bolt Torque Calculator
Calculate tightening torque for metric bolts based on clamp load, thread pitch, and friction coefficient.
Shaft Power & Torque
Convert between shaft power, torque, and rotational speed. Calculate shaft diameter from transmitted torque.
Gear Ratio Calculator
Calculate output speed, torque, and gear efficiency for single-stage or multi-stage gear drives.
Belt & Pulley Drive
Calculate belt speed, tensions, and pulley sizes for V-belt or flat-belt power transmission.
Bearing Life (L10)
Calculate L10 and L50 bearing life in hours using the basic dynamic rating ISO 281 method.
Compression Spring Calculator
Calculate spring rate, stress, and deflection for a helical compression spring.
Hydraulic Cylinder Force
Calculate extend and retract force of a hydraulic cylinder from bore, rod diameter, and system pressure.
Hydraulic Cylinder Flow Rate
Calculate hydraulic flow rate required for a target cylinder extension/retraction speed.
Pressure Vessel Wall Thickness
Calculate minimum wall thickness for a cylindrical pressure vessel per ASME Sec. VIII Div. 1.
Pipe Flow (Hazen-Williams)
Calculate flow velocity, flow rate, and head loss for water in a pipe using the Hazen-Williams equation.
Fillet Weld Size
Calculate the minimum fillet weld leg size to carry a shear or tensile load per AS/NZS 1554 or AWS D1.1.
Weld Heat Input
Calculate arc energy and heat input per unit length from welding parameters.
Weld Preheat Temperature
Calculate minimum preheat temperature from carbon equivalent (CE) using the AWS or Ito-Bessyo formula.
Electrode / Wire Consumption
Estimate weld metal volume, electrode weight, and deposition rate for a weld joint.
Welding Cost Estimator
Estimate total welding cost including labour, consumables, gas, and equipment from deposition rate and weld volume.
Water Supply Pipe Sizing
Size water supply pipes by fixture unit loading and velocity limits per AS/NZS 3500 or UPC.
Drainage Pipe Sizing
Size sanitary drain pipes by fixture unit loading and minimum grade per AS/NZS 3500.2 or IPC.
Hot Water System Sizing
Size a storage hot water system (kW and litres) for a residential or commercial building.
HVAC Duct Sizing
Size rectangular or circular ducts from airflow and target velocity using the equal friction method.
Heat Pump vs Resistance Heater
Compare annual running costs of a heat pump versus direct electric resistance heater or gas boiler.
Boiler Output Sizing
Estimate required boiler output (kW) for space heating from building fabric heat loss.
Concrete Volume & Cost
Calculate concrete volume and materials cost for slabs, footings, columns, and beams.
Formwork Lateral Pressure
Calculate maximum lateral pressure on vertical formwork from fresh concrete, per ACI 347R or CIRIA C700.
Reinforcement Quantity
Estimate reinforcing bar quantity (kg) for slabs, beams, and columns from reinforcement ratio.
Concrete Curing & Strength Gain
Estimate concrete strength gain over time and minimum curing period at a given temperature.
Cut and Fill Volume
Calculate earthwork cut and fill volumes for a pad or strip formation using the prismoidal method.
Grade & Slope Converter
Convert between percentage grade, degree angle, 1:n ratio, and rise/run measurements.
Batter Slope & Setback
Calculate the horizontal setback distance for a cut or fill batter slope from face height and batter ratio.
Bearing & Distance to Coordinates
Calculate easting/northing coordinates from a known start point, bearing, and distance.
Polygon Area from Coordinates
Calculate the area of a closed polygon from a list of easting/northing coordinate pairs using the Shoelace formula.
Noise Exposure Dose
Calculate daily noise dose (%) and equivalent LAeq from multiple noise sources and exposure times.
NIOSH Lifting Equation
Calculate the Recommended Weight Limit (RWL) and Lifting Index (LI) using the revised NIOSH lifting equation.
Silica Dust Exposure (TWA)
Calculate 8-hour TWA for respirable crystalline silica and compare to workplace exposure standards.
Fall Arrest Clearance Distance
Calculate minimum clearance distance below anchor for a fall arrest system to prevent ground strike.
Construction Activity Carbon
Estimate embodied carbon from common construction materials and plant usage.
Job Quote Builder
Build a trade job quote from labour, materials, subcontractors, plant, and overhead with markup.
Markup vs Margin Calculator
Convert between gross profit margin and cost markup percentage, and calculate sell price from cost.
Plant Hire vs Buy
Compare the cost of hiring equipment vs purchasing outright, accounting for utilisation, depreciation, and maintenance.
Asset Depreciation
Calculate straight-line and diminishing value depreciation schedules for plant, equipment, and vehicles.
Plant Fuel Cost Per Hour
Calculate hourly fuel cost for diesel or petrol plant and machinery from engine size and load factor.
Engine Torque & Power
Convert between engine torque, power, and RPM. Calculate gear-end wheel torque and tractive effort.
Engine Compression Ratio
Calculate compression ratio from bore, stroke, clearance volume, and head gasket parameters.
Tyre Size & Speedometer Error
Calculate rolling circumference, effective radius, and speedometer error when changing tyre sizes.
Air Compressor Sizing
Size an air compressor (L/min FAD) and receiver tank for a list of pneumatic tools and duty cycles.