step 1 / choose a discipline
Engineering calculators, organised by topic.
Start with structural, geotechnical, hydraulics, site and construction, or utilities. Each hub then narrows the choice to an analysis type, design material, load case, or code route.
calculator topics
Choose your discipline.
Structural has the deepest route today. The same hub pattern is ready to scale as more civil engineering tools are added.
01 / STRUCTURAL54 tools
Structural engineering
Move from beam and column analysis to preliminary reinforced-concrete design, geometric section properties, and international-code subsets.
Loading analysis · Structural design Choose a structural branch 02 / GEOTECHNICAL5 toolsGeotechnical engineering
Screen footing pressure and capacity, Rankine earth pressure, and retaining-wall stability.
Foundations · Earth pressure · Retaining walls Open geotechnical 03 / HYDRAULICS12 toolsHydraulics & stormwater
Calculate channel and pipe flow, head loss, critical depth, weir flow, hydrostatic thrust, and runoff.
Open channels · Pipes · Stormwater Open hydraulics 04 / SITE5 toolsSite & construction
Estimate concrete, reinforcement, earthwork, and grade geometry for practical site planning.
Quantities · Reinforcement · Setting out Open site tools 05 / UTILITIES1 toolEngineering utilities
Convert common lengths, areas, forces, and pressures before using them in a calculation.
Unit conversion Open utilitiesall calculators / direct access
Jump straight to a calculation.
Every calculator remains directly available for search, bookmarks, and shared links. Results are transparent preliminary checks; verify the governing code and project requirements before design use.
Structural engineering 54
- Simply supported beam calculatorUDL, central point load, shear, moment and deflection
- Simply supported beam reaction calculatorUDL and an off-centre point load
- Simply supported triangular-load calculatorReactions, moment and elastic deflection
- Simply supported linear-load patch calculatorPartial triangular or trapezoidal load with elastic response
- Fixed-fixed beam UDL calculatorEnd moments, reactions and midspan deflection
- Fixed-fixed beam point-load calculatorCentral point load with full end fixity
- Cantilever beam calculatorEnd-load moment and elastic deflection
- Cantilever UDL calculatorFull-span uniform load and free-end movement
- Cantilever triangular-load calculatorLoad rising toward the free end
- Propped cantilever UDL calculatorCompatibility reactions, moments and deflection
- Partial UDL zone calculatorOne or two loaded segments anywhere on a simple span
- Multiple point-load beam calculatorUp to three equal or unequal loads and positions
- Central triangular-load calculatorSymmetric tent-shaped distributed load
- Beam end-moment calculatorPrescribed signed end moments with UDL or point load
- Fixed beam arbitrary point-load calculatorOff-centre reactions, end moments and load deflection
- Cantilever arbitrary point-load calculatorLoad-point and free-end movement
- Cantilever combined-load calculatorUDL, point load and free-end moment superposition
- Propped cantilever point-load calculatorCompatibility actions for any load position
- Overhang beam calculatorMovable supports, full-length UDL and point load
- Overhang-end UDL calculatorUDL acting only on the overhang
- Two-span continuous beam calculatorIndependent full-span UDLs and middle-support moment
- Two-span point-load calculatorPoint loads on either continuous span
- Two-span partial-UDL calculatorIndependent movable uniform-load patch on each span
- Two-to-four-span UDL calculatorContinuous-beam support moments and sagging response
- Bending stress calculatorElastic stress from moment and section modulus
- RC beam flexural capacity calculatorPreliminary, code-neutral moment resistance
- RC beam reinforcement calculatorPreliminary, code-neutral tension-steel area
- RC beam section design calculatorEurocode and declared SDMHR material profiles; section, bending, shear and torsion comparisons
- Eurocode concrete cover calculatorVerified bond minimum, durability class and National Annex adjustments
- Hong Kong highway concrete cover calculatorSDMHR Table 5.2 nominal cover, crack limits and footnote adjustments
- Steel beam design calculatorSection inputs, cross-section resistance, lateral stability and serviceability in one declared workflow.
- Eurocode 3 steel section calculatorDeclared first-generation EN 1993-1-1 subset
- Eurocode 3 column buckling calculatorTwo-axis flexural buckling with explicit curves
- Eurocode 3 lateral-torsional buckling calculatorGeneral member resistance using supplied Mcr
- Hong Kong RC beam design calculatorSection, reinforcement and workbook-based checks
- Hong Kong RC column design calculatorColumn section and inspectable calculation
- Hong Kong RC slab design calculatorSlab reinforcement and workbook-based checks
- Hong Kong RC wall design calculatorWall bending and shear calculation
- Hong Kong RC beam flexure calculatorBounded HK Concrete Code section check
- Hong Kong RC beam shear calculatorConcrete stress, vertical links, and spacing
- Hong Kong one-way RC slab calculatorOne-metre strip flexure and concrete-only shear screen
- Hong Kong steel section calculatorBounded low-shear Class 1–2 resistance check
- Hong Kong steel member design calculatorWorkbook-based beam/column section, stability and serviceability checks
- Hong Kong weld design calculatorFillet-weld group actions and resistance with inspectable equations
- Hong Kong bolt design calculatorBolt-group shear, tension, bearing and combined demand
- Hong Kong plate design calculatorConnection-plate checks adapted from the supplied workbook
- Euler column buckling calculatorIdeal elastic critical load and slenderness
- Column axial stress calculatorGross-area stress and utilisation screen
- Rectangular section properties calculatorArea, second moment, section modulus and radius
- Circular section properties calculatorSolid-circle area, inertia and section modulus
- I-section properties calculatorStrong- and weak-axis geometric properties
- T-section properties calculatorCentroid, inertia and top/bottom section moduli
- L-section properties calculatorAngle area, centroid and axis properties
- Slab load to beam calculatorArea load, tributary width and line load
Site & construction 5
- Concrete volume calculatorGeometric volume, allowance and order quantity
- Rebar weight calculatorBar length, diameter, quantity and steel mass
- Rebar spacing and quantity calculatorBar count, spacing and cut-length estimate
- Earthwork volume calculatorAverage-end-area cut or fill quantity
- Grade and slope calculatorRise, run, percentage, angle and ratio
Hydraulics & stormwater 12
- Manning open-channel flow calculatorRectangular-channel discharge and velocity
- Manning trapezoidal channel calculatorFlow from base width, depth and side slopes
- Manning normal depth calculatorSolve rectangular-channel depth for target flow
- Rectangular critical depth calculatorCritical depth, velocity and Froude number
- Rectangular weir flow calculatorFree-flow discharge from head and crest width
- Manning full-pipe flow calculatorCircular-pipe capacity and velocity
- Manning pipe diameter calculatorRequired full-flow diameter for target discharge
- Part-full pipe flow calculatorDepth ratio, discharge and velocity
- Darcy-Weisbach head loss calculatorPipe friction and minor losses
- Hazen-Williams head loss calculatorWater-pipe friction from flow, diameter and C value
- Hydrostatic wall pressure calculatorPressure, thrust, centre of pressure and moment
- Rational Method stormwater calculatorPeak runoff from coefficient, intensity and area
Geotechnical engineering 5
- Shallow footing pressure calculatorAverage bearing pressure and utilisation
- Terzaghi bearing capacity calculatorUltimate and preliminary allowable capacity
- Rankine active earth pressure calculatorCoefficient, thrust and overturning moment
- Retaining wall stability calculatorSliding, overturning and base-pressure screen
- Retaining wall design calculatorWorkbook-based wall geometry, earth actions and inspectable stability checks
Engineering utility 1
- Civil engineering unit converterLength, area, force and pressure conversions