Engineering Calculators — Electrical, Mechanical & Civil
Electrical, mechanical and civil calculators for beam loads, wire gauge, Ohm law and torque — formula and worked steps on each page.
Sizing, loads, currents and flows — the calculations engineers redo a dozen times a day. Each tool cites its governing formula (Darcy-Weisbach for pipe loss, Euler for buckling, standard wire-gauge tables) and states the safety margins it does NOT include, so a code check still belongs with a licensed engineer.
Voltage Drop Calculator
Calculate voltage drop in cable
Power Factor Calculator
Calculate power factor
Gear Ratio Calculator
Calculate gear ratio
Torque Calculator
Calculate torque with force, radius and angle
LED Resistor Calculator
Calculate LED series resistor
Capacitor Calculator
Calculate capacitance
Battery Life Calculator
Estimate battery life
Wire Gauge Calculator
Calculate wire gauge
RPM Calculator
Calculate rotational speed
Horsepower Calculator
Calculate horsepower
Inductor Calculator
Calculate inductance
Impedance Calculator
Calculate RC/RL impedance
Beam Load Calculator
Calculate beam stress
Hydraulic Calculator
Calculate hydraulic pressure
Thermal Expansion
Calculate thermal expansion
kVA to kW Converter
Convert apparent power kVA to real power kW
Belt Length Calculator
Calculate V-belt length for two pulleys
Flow Rate Calculator
Calculate pipe flow rate from velocity and area
Sound Level Addition
Add two sound levels in decibels
Shaft Power Calculator
Calculate power from torque and RPM
Spring Rate Calculator
Calculate spring constant (Hooke's law)
Resonant Frequency Calculator
Calculate LC circuit resonant frequency
Transformer Ratio Calculator
Calculate transformer turns ratio
Hydraulic Power Calculator
Calculate pump hydraulic power
Stress & Strain Calculator
Calculate stress, strain and Young's modulus
Beam Deflection (Simply Supported)
Max deflection of a uniformly loaded beam
Euler Buckling Load
Critical load for column buckling
Pipe Flow Rate (Darcy-Weisbach)
Pressure drop and velocity in pipe flow
Steel Weight Calculator
Weight of steel plates, bars, and tubes
Concrete Mix Design
Cement, sand, and gravel quantities for a mix
Structural Load Calculator
Dead, live, and wind load combinations (LRFD)
Electrical Energy Cost
Electricity cost of an appliance
Resistor Combination
Series and parallel resistance
Capacitor Energy
E = ½CV² energy stored in a capacitor
Inductor Energy
E = ½LI² energy stored in an inductor
RC Time Constant
τ = RC for capacitor charging/discharging
Cable Sizing Calculator
Wire size from current and voltage drop
Ventilation CFM Calculator
Airflow needed for room ventilation
Torque Wrench Setting
Adjusted torque when using an extension
Bearing Load Rating
Required dynamic load rating from bearing life
Engine Efficiency Calculator
Thermal efficiency and BSFC
Pump Power Calculator
Hydraulic power and motor size for pumps
Tank Volume Calculator
Volume of cylindrical and rectangular tanks
Heat Exchanger (LMTD)
Log mean temperature difference method
PCB Trace Width Calculator
IPC-2221 trace width for a given current
Bolt Torque Calculator
Clamping force from bolt torque
Pulley System Calculator
Effort needed with multiple pulley ropes
Lever Calculator
Fulcrum position or effort for a class-1 lever
Formulas, worked examples aur edge cases ke liye: Engineering guides
Frequently asked questions
Do these results include a safety factor?
No — the calculators return the raw computed value. Safety factors belong to the design code you are working to, not to the formula, so apply the factor your standard requires rather than assuming one is built in. Never use a calculated figure as a substitute for the governing code or a qualified engineer's check.
Why does wire gauge change so much between AWG and mm²?
AWG is a logarithmic scale that gets larger as the number gets smaller, while mm² is a direct area measurement. They are not linearly interchangeable, so always convert with a table rather than a ratio — and check whether a quoted gauge is the conductor area or the overall cable size.
How much voltage drop is acceptable on a run?
Common guidance targets a few per cent of nominal voltage at the far end, with tighter limits for sensitive loads, but the exact figure comes from your local wiring rules. The calculator shows the drop for a given conductor and length so you can compare it against the limit that applies to you.
Last updated