Engineering Tools.
Professional Grade. Free.
Civil & structural calculators, electrical design tools, mechanical engineering formulas, HVAC sizing, software cost estimators and more — all browser-based, zero signup.
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Civil & Structural
18 toolsBeam design, concrete, foundations, earthworks, ASCE & ACI codes
Beam Deflection Calculator
Simply supported, cantilever & continuous beams
Concrete Mix Design
M10–M40 grade cement:sand:aggregate ratios
Column Load Capacity
Axial, buckling & slenderness ratio
Retaining Wall Stability
Overturning & sliding check
Foundation Bearing Capacity
Terzaghi & Meyerhof equations
Steel Section Properties
I, S, Z, r for W, S, C, L sections
Rebar Quantity Estimator
Spacing, cover & lap length
Concrete Volume Calculator
Slab, column, beam & footing volumes
Wind Load Calculator
ASCE 7 / Eurocode EN 1991
Truss Member Force Solver
Method of joints & sections
Moment of Inertia Calculator
Composite & custom cross-sections
Pile Load Capacity
Skin friction & end bearing
Slab Reinforcement Designer
One-way & two-way slab design
Earthwork Cut & Fill
Prismoidal & average-end area method
Asphalt Pavement Thickness
CBR & AASHTO design method
Slope Stability (FOS)
Bishop's simplified method
Soil Bearing Pressure
Net vs gross ultimate bearing
Construction Cost Estimator
Material + labor by project type
Electrical Engineering
18 toolsPower systems, wiring, solar, protection, NEC & IEC standards
Ohm's Law Calculator
V, I, R, P — all combinations
Wire & Cable Size Calculator
AWG & mm² current capacity
Voltage Drop Calculator
NEC & IEC compliant
3-Phase Power Calculator
kW, kVA, kVAR & power factor
Transformer Sizing Tool
kVA selection & turns ratio
Motor Starting Current
Inrush & locked-rotor current
Solar Panel & Battery Sizing
kWh/day, panel count, bank size
LED Energy Savings
kWh vs cost comparison
Circuit Breaker Sizing
NEC 80% rule & coordination
Capacitor Bank Sizing
kVAR for power factor correction
UPS Battery Backup Calculator
Runtime & AH estimation
Power Factor Correction
Capacitor size from kW & PF
Short Circuit Current (SCC)
Symmetrical fault calculation
Conduit Fill Calculator
NEC Chapter 9 Table compliance
PV System ROI Calculator
Payback period & IRR
Battery State of Charge
DoD, cycles & capacity fade
Earthing / Grounding Resistance
Rod, grid & plate electrodes
Load Schedule / Panel Board
Branch circuit load estimator
Mechanical Engineering
18 toolsFasteners, thermodynamics, fluid mechanics, machining, ASME
Bolt Torque Calculator
Clamping force vs applied torque
Gear Ratio Calculator
Speed, torque & efficiency
HP / kW Converter
Shaft power conversions
Pressure Vessel Thickness
ASME Section VIII Div. 1
Fluid Flow Rate Calculator
Bernoulli & continuity equation
Heat Transfer Calculator
Conduction, convection, radiation
Pump Head & Flow Sizing
Centrifugal pump selection
Spring Constant Calculator
Hooke's law & spring design
Belt & Pulley Speed
V-belt drive design
CNC Feeds & Speeds
SFM, RPM, feed per tooth
Tolerance Stack-up
Worst-case & RSS method
Fatigue Life Estimator
S-N curve & Miner's rule
Thermal Expansion Calculator
Linear & volumetric expansion
Bearing Life (L10) Calculator
Dynamic load rating & rpm
Stress & Strain Calculator
Young's modulus, yield, UTS
Reynolds Number Calculator
Laminar vs turbulent flow
Vibration Frequency Tool
Natural frequency & resonance
Hydraulic Cylinder Force
Force, speed & flow rate
HVAC & Building Services
10 toolsCooling loads, ductwork, insulation, ventilation, ASHRAE standards
Cooling Load Calculator
BTU/hr for room or building
Heating Load Estimator
Heat loss by degree-day method
Duct Sizing Calculator
Velocity & static pressure method
Psychrometric Calculator
Dew point, enthalpy, humidity
COP / EER Calculator
Cooling efficiency metrics
U-Value / R-Value Calculator
Insulation thermal resistance
Ventilation Rate Calculator
ACH & ASHRAE 62.1 compliance
Chilled Water Pipe Sizing
Flow & velocity for CHW loops
Boiler Efficiency Calculator
Combustion & stack loss
Building Energy Audit Tool
kWh savings by intervention
Oil, Gas & Chemical
10 toolsPipe hydraulics, heat exchangers, process design, API standards
Pipe Pressure Drop Calculator
Darcy-Weisbach & Hazen-Williams
Orifice Plate Flow Calculator
ISO 5167 standard
Heat Exchanger Sizing
LMTD & NTU method
Gas Compressor Power
Polytropic & adiabatic compression
Pump NPSH Calculator
Available vs required NPSH
Flare Stack Sizing Tool
API 521 relief load method
Distillation Column Estimator
Theoretical plates & reflux ratio
Gas Molecular Weight Calc
Mixture MW & density
Steam Table Lookup Tool
Saturated & superheated steam
Relief Valve Sizing (PSV)
API 520/521 methodology
Geotechnical & Environmental
16 toolsSoil mechanics, foundations, slope stability, hydrology
Soil Bearing Capacity (Terzaghi)
General & local shear failure
Settlement Calculator
Immediate & consolidation settlement
Slope Stability (Bishop)
Circular failure surface FOS
Lateral Earth Pressure
Rankine & Coulomb Ka, Kp
Liquefaction Potential Checker
SPT-based simplified method
Pile Driving Formula Tool
Hiley & ENR formula
Permeability / Seepage Calculator
Darcy's law for soil
SPT N-Value to Parameters
Phi, relative density conversion
Stormwater Runoff Calculator
Rational method Q = CiA
Water Demand Estimator
Per capita & fire flow demand
Water Tank Sizing Tool
Overhead & underground tanks
Wastewater Flow Estimator
BOD, COD & hydraulic loading
Solar Irradiance & PV Yield
kWh/day by location & tilt
Carbon Footprint Calculator
Buildings, transport & process
Flood Frequency Analysis
Return period & peak discharge
Water Quality Index Tool
WQI from pH, DO, BOD inputs
Electronics & Telecommunications
10 toolsPassive components, RF, PCB design, filters, signal processing
Resistor Color Code Decoder
4-band & 5-band resistors
RC / RL / LC Filter Designer
Cutoff frequency & impedance
Antenna Length Calculator
Half-wave dipole & Yagi
PCB Trace Width Calculator
IPC-2221 current & temperature
555 Timer Calculator
Astable & monostable modes
dB / Signal Loss Calculator
RF link budget tool
Op-Amp Gain Calculator
Inverting & non-inverting config
LED Resistor Calculator
Series resistor for any LED
Capacitor Charge Time
RC time constant & tau
Zener Voltage Regulator
Resistor & power dissipation
Aerospace & Automotive
8 toolsAircraft performance, vehicle dynamics, propulsion, aerodynamics
Thrust-to-Weight Ratio
Aircraft performance estimation
Drag Coefficient Estimator
Cd for basic body shapes
Wing Loading Calculator
Stall speed & lift coefficient
Vehicle Fuel Economy Estimator
MPG / L/100km from driving data
EV Range Calculator
kWh/km & battery range
Engine Horsepower Estimator
Torque & RPM to HP/kW
Mach Number / Speed Converter
IAS, TAS, Mach at altitude
Braking Distance Calculator
Reaction time & deceleration
Software & IT Engineering
10 toolsCloud costs, security, infrastructure sizing, DevOps — highest CPC
Cloud Cost Estimator
AWS vs Azure vs GCP comparison
Server Rack Power & Cooling
PUE & cooling capacity
Network Bandwidth Calculator
Throughput & latency estimator
API Load / RPS Calculator
Requests/sec & infrastructure
Database Storage Estimator
Row count to GB/TB estimator
Cyber Security Risk Calculator
CVSS score & risk rating
SaaS Pricing / LTV Calculator
CAC, LTV & payback period
CI/CD Pipeline Cost Estimator
Build minutes & monthly cost
Docker / K8s Resource Sizing
CPU & memory limits planner
Password Entropy Calculator
Bits of entropy & crack time
Project & Construction Management
8 toolsScheduling, costing, EVM, BOQ, CPM, depreciation
Critical Path Method (CPM)
Float & project duration
BOQ / Material Take-off Tool
Quantity & cost breakdown
Project ROI Calculator
NPV, IRR & payback period
Earned Value Management (EVM)
CPI, SPI & EAC metrics
Labour Productivity Estimator
Output per man-hour
Crane Lift Capacity Checker
Load chart & radius tool
Contractor Markup Calculator
Overhead, profit & bid price
Depreciation Calculator
SLM, WDV & MACRS methods
Why Engineers Trust Our Free Online Calculators
Our engineering tool suite covers all major disciplines with formulas validated against industry standards including ASCE 7, ACI 318, ASME, NEC, API 520/521, IEC and ASHRAE. Each calculator shows the formula used so you can verify results.
- ✓Civil & Structural: beam deflection, concrete mix, column capacity, retaining walls, pile design
- ✓Electrical: Ohm's law, voltage drop, 3-phase power, solar sizing, protection coordination
- ✓Mechanical: gear ratios, pressure vessels, heat transfer, CNC feeds, fatigue life
- ✓HVAC: cooling loads, duct sizing, psychrometrics, U-values, boiler efficiency
- ✓Software & IT: cloud costs, API load, database sizing, CVSS risk, SaaS metrics
- ✓Geotechnical, Oil & Gas, Electronics, Aerospace and Project Management included