Search Calculators

The Concrete Anchor Capacity Calculator compares concrete breakout against steel capacity for an anchor in tension, including the edge distance effect.

The Concrete Block Wall Calculator determines block quantities, face-shell mortar and grout volume for reinforced or unreinforced blockwork.

The Column Interaction Calculator determines the axial capacity and balanced point of a rectangular reinforced concrete column.

The Concrete Mix Design Calculator estimates the water-cement ratio and the quantities of cement, water, sand and coarse aggregate required for a given target strength, slump and volume.

The Concrete Modulus of Elasticity Calculator determines the static modulus Ec of concrete from its compressive strength and density, using the ACI 318 density-based expression.

The Concrete Strength Calculator estimates the 28-day compressive strength of concrete from its water-cement ratio, and the strength developed at any age using the ACI 209 maturity function.

The Concrete Volume Calculator determines the net and total concrete volume for a rectangular slab or footing, applies a waste allowance, and converts the result into bag counts and ready-mix truck loads.

The Crack Width Estimator predicts the surface crack width in a reinforced concrete flexural member from the service steel stress, concrete cover and bar spacing, using the Gergely-Lutz expression.

The Concrete Creep and Shrinkage Calculator estimates the creep coefficient and shrinkage strain, and the total long-term deformation.

The Development Length Calculator determines the straight embedment length required to develop the yield strength of a deformed reinforcing bar in tension, using the ACI 318 simplified expression.

The Footing Size Calculator determines the plan size of a square pad footing, allowing for its own weight and for an applied moment.

The Prestress Loss Calculator separates the four long-term losses in a prestressed member and gives the effective tendon stress remaining.

The Punching Shear Calculator determines the critical perimeter and nominal two-way shear capacity of a concrete slab at an interior column, following the ACI 318 provisions.

The Rebar Spacing Calculator converts a required steel area into a practical bar arrangement, returning the area per bar, the number of bars per metre, the centre-to-centre spacing and the reinforcement ratio.

The Slab Thickness Calculator determines the minimum thickness of a one-way concrete slab from its span and support conditions, applying the ACI 318 span-to-depth ratios and the reinforcement yield strength modifier.

The Asphalt Tonnage Calculator converts area and compacted thickness into tonnage, with the loose laying depth and estimated cost.

The Brick Wall Calculator determines brick quantity and mortar volume from wall area, brick dimensions and joint thickness.

The Crane Capacity Calculator determines lifting capacity at a given radius from the rated load moment, and the utilisation of a planned lift.

The Cut & Fill Calculator estimates excavation and embankment volumes between two cross-sections using the average end area method, and reports the net balance.

The Dewatering Flow Calculator estimates steady-state groundwater inflow to a circular excavation using the Dupuit-Forchheimer equation.

The Drywall Estimator calculates plasterboard sheets, studs, screws and jointing materials from wall area and board dimensions.

The Earthwork Volume Calculator computes excavation volume for a rectangular dig, then converts it to loose volume, truck loads and approximate weight.

The Lumber Volume Calculator converts timber section, length and quantity into volume in cubic metres and board feet, with cost.

The Paint Coverage Calculator determines how much paint a job needs, correcting the theoretical quantity for application transfer efficiency.

The Retaining Wall Calculator determines the Rankine active earth pressure coefficient and force on a gravity retaining wall, and checks it against overturning and sliding.

The Scaffolding Load Calculator determines the load carried by each bay and each standard from the duty classification and bay geometry.

The Slope Stability Calculator determines the factor of safety of a slope against shallow translational failure using the infinite slope method, together with the maximum angle at which that slope remains stable.

The Soil Bearing Capacity Calculator determines ultimate and net allowable bearing pressure from soil strength parameters and footing geometry.

The Soil Compaction Calculator converts a field wet density and moisture content into dry density, then reports relative compaction against the laboratory Proctor maximum.

The Trench Volume Calculator determines excavation and backfill volumes for a trench with battered or vertical sides, allowing for pipe displacement.

The AWG Wire Size Converter turns an American Wire Gauge number into conductor diameter, cross-sectional area, resistance per kilometre and voltage drop.

The Battery Bank Sizing Calculator determines the storage capacity needed for a given daily load and autonomy period, allowing for depth of discharge and efficiency.

The Power Factor Correction Calculator sizes the capacitor bank needed to raise power factor from its present value to a target, in kVAr and microfarads.

The Conduit Fill Calculator determines the percentage of a conduit's cross-section occupied by conductors, and the maximum number that may be installed.

The LED Resistor Calculator determines the series resistor for one or more LEDs, snapping to the nearest E12 preferred value and reporting the resulting current.

The Motor Full Load Amps Calculator determines the running current of a three-phase or single-phase motor from its shaft power, with starting current and breaker size.

The Ohm's Law Calculator solves for whichever of voltage, current or resistance is unknown, given the other two, and returns the power dissipated in the circuit.

The Power Factor Calculator determines the power factor from a phase angle and resolves the apparent power into its real and reactive components for a single-phase circuit.

The Resistor Colour Code Calculator decodes four colour bands into a resistance value with tolerance limits, and checks the result against the E24 preferred series.

The Short Circuit Current Calculator determines the prospective fault current at a transformer's terminals and at a point downstream, from the transformer impedance and cable run.

The Solar Panel Output Calculator estimates the daily and annual energy from a photovoltaic array, with specific yield and the aperture area required.

The Transformer Calculator determines the turns ratio, primary and secondary currents and output power of a single-phase transformer from its voltages, kVA rating and efficiency.

The Voltage Divider Calculator determines the output of a resistive divider both unloaded and with a load, and reports the loading error the load introduces.

The Voltage Drop Calculator determines the volt drop along a single-phase circuit from the load current, one-way cable length and conductor resistance, with the percentage drop and power loss.

The Wire Size Calculator estimates the conductor cross-section required by current density and by a 3% voltage drop limit, then recommends the next standard size above whichever governs.

The Bernoulli Equation Calculator applies the energy equation between two points in a flow system, solving for the downstream pressure from the upstream conditions, velocity change, elevation change and head loss.

The Catchment Runoff Calculator computes storm runoff depth and volume using the SCS Curve Number method, from rainfall depth, curve number and catchment area.

The Culvert Design Calculator computes the full-bore capacity and velocity of a circular culvert under outlet control, and the diameter required for a given design flow.

The Froude Number Calculator classifies open channel flow as subcritical, critical or supercritical, and returns the critical depth and specific energy.

The Head Loss Calculator determines friction head loss in a pipe using the Darcy-Weisbach equation, and converts it into pressure drop, loss per metre and the pumping power required to overcome it.

The Manning's Equation Calculator determines the flow velocity and discharge in a rectangular open channel from its dimensions, slope and roughness coefficient.

The NPSH Calculator determines the net positive suction head available at a pump, the margin over its requirement, and the maximum suction lift the system can sustain.

The Open Channel Velocity Calculator computes velocity, discharge and Froude number for a trapezoidal channel using Manning's equation.

The Orifice Flow Calculator determines the discharge through a small orifice under a given head, using Torricelli's theorem with a discharge coefficient.

The Pipe Flow Calculator determines flow velocity, cross-sectional area, Reynolds number and flow regime for a circular pipe running full, from the flow rate, diameter and fluid viscosity.

The Rainfall-Runoff Calculator determines peak stormwater discharge from a catchment using the Rational Method, along with the rainfall and runoff volumes over one hour.

The Reynolds Number Calculator determines whether pipe flow is laminar, transitional or turbulent, and returns the corresponding Darcy friction factor.

The Settling Velocity Calculator determines how fast a particle settles in a fluid, using Stokes' law and correcting it with an iterative drag solution beyond its valid range.

The Water Hammer Calculator determines the surge pressure from rapid valve closure using the Joukowsky equation, with the critical closure time and relief for slower closure.

The Weir Flow Calculator determines discharge over a rectangular sharp-crested weir, applying the Francis correction for end contractions.

The Air Receiver Sizing Calculator determines stored free air, compressor cycling rate and duty cycle from receiver volume, pressure band, delivery and demand.

The Bearing Life Calculator determines the ISO 281 basic rating life L10 from the dynamic load rating, equivalent load and rotational speed.

The Belt Drive Calculator determines the speed ratio, output speed, required belt length and arc of contact on the smaller pulley for an open belt drive between two pulleys.

The Gear Ratio Calculator determines the ratio between two meshing gears from their tooth counts, and the resulting output speed, output torque and mechanical advantage after efficiency losses.

The Heat Transfer Calculator determines steady-state conductive heat loss through a building element, with U-value, thermal resistance and heat flux.

The HVAC Duct Sizing Calculator determines duct size from airflow and velocity, with the rectangular equivalent and the friction pressure drop.

The Hydraulic Cylinder Force Calculator determines extend and retract force from bore, rod diameter and pressure, with rod speeds at a given flow.

The Kinetic Energy Calculator determines the energy and momentum of a moving mass, with the stopping force required over a given distance.

The Compound Pulley Drive Calculator determines the output speed and overall ratio of a two-stage belt drive, with intermediate speed and belt speed.

The Pump Power Calculator determines hydraulic, shaft and electrical power for a pumping duty, together with the specific energy per cubic metre.

The Shaft Deflection Calculator determines bending deflection, stress and support slope for a simply supported shaft carrying a central point load.

The Spring Constant Calculator solves Hooke's law for whichever of force, spring constant or displacement is unknown, given the other two, and returns the elastic potential energy stored.

The Thermal Expansion Calculator determines the change in length of a member under a temperature change, and the stress that develops if that movement is fully restrained.

The Torque Calculator determines torque either from a force acting at a radius, or from transmitted power and rotational speed, returning torque, power and angular velocity together.

The V-Belt Tension Calculator determines effective, tight-side and slack-side tensions and the resultant shaft load for a V-belt drive.

The Beam Deflection Calculator determines the maximum deflection of a simply supported beam carrying a concentrated point load at midspan, using Euler-Bernoulli beam theory, and checks the result against the L/360 serviceability limit.

The Bolt Shear Capacity Calculator determines the nominal shear strength of a single bolt in one shear plane, using the gross bolt area and the nominal shear stress from AISC 360 Table J3.2.

The Cable Tension Calculator determines the horizontal and maximum tension in a cable carrying a uniformly distributed load, using the parabolic approximation appropriate to suspension structures.

The Column Buckling Calculator determines the Euler critical buckling load of a slender compression member, along with its effective length, radius of gyration, slenderness ratio and critical stress.

The Fixed End Moment Calculator determines the support moments developed in a beam with both ends fully fixed, under a uniformly distributed load, a central point load, or both acting together.

The Moment of Inertia Calculator determines the second moment of area of a solid or hollow rectangular section about both principal axes, together with the cross-sectional area and radius of gyration.

The Portal Frame Analysis Calculator determines the column base shear and maximum column moment in a single-bay rigid frame under lateral load, using the classical Portal Method approximation.

The Section Modulus Calculator determines both the elastic section modulus S and the plastic section modulus Z of a rectangular cross-section, the two properties that convert bending moment into stress and into capacity.

The Snow Load Calculator determines the flat roof snow load and the sloped roof snow load from a ground snow load and roof pitch, following the ASCE 7 Chapter 7 procedure.

The Steel Beam Design Calculator determines the nominal and design flexural capacity of a compact steel beam under AISC LRFD, reports the demand/capacity ratio, and returns the plastic section modulus required to carry a given moment.

The Torsion and Shear Stress Calculator determines the maximum torsional shear stress and the angle of twist in a solid circular shaft under an applied torque.

The Truss Analysis Calculator determines support reactions, maximum midspan moment, peak chord force and panel length for a simply supported parallel-chord truss under a uniformly distributed load.

The Fillet Weld Strength Calculator determines the effective throat, capacity per unit length and total nominal capacity of a fillet weld loaded in shear, following AISC 360 §J2.4.

The Wind Load Calculator determines the ASCE 7 velocity pressure at a given height above ground for Exposure C terrain, together with the reference force on an exposed area.

The Wood Joist Span Calculator determines the maximum allowable span of a rectangular timber floor joist, checking the bending stress limit and the L/360 deflection limit separately and reporting whichever governs.