138 Free Engineering Tools — Units, Forces & Materials
Technical calculators for unit conversions, material properties, and engineering formulas. No signup required.
Electrical Engineering
Circuits, components, power & wiring tools
Ohm's Law Calculator
Solve V, I, R or P from any two values
Voltage Divider Calculator
Compute output voltage of a resistive divider
Current Divider Calculator
Compute branch current in parallel resistors
SoonResistor Color Code Decoder
Decode 4, 5 and 6-band resistor color codes
SoonResistor Series/Parallel Calculator
Equivalent resistance for any network
Capacitor Calculator
Energy, charge and impedance of a capacitor
Inductor Calculator
Energy stored and reactance of an inductor
RC Time Constant Calculator
Tau, charge & discharge of RC circuits
SoonLC Resonance Calculator
Resonant frequency of LC tank circuits
Power Factor Calculator
Real, reactive, apparent power & PF correction
SoonThree-Phase Power Calculator
Star/Delta voltages, currents and power
SoonTransformer Ratio Calculator
Turns ratio, voltage and current relations
SoonWire Gauge Current Capacity
AWG ampacity reference tables
SoonFuse Rating Calculator
Select fuse rating for a load
SoonPCB Trace Current Calculator
IPC-2221 trace width for current
SoonHeat Sink Thermal Calculator
Thermal resistance and junction temperature
Electronic Components
Op-amps, timers, transistors & semiconductor references
Op-Amp Circuit Reference
Common op-amp topologies & gain equations
Soon555 Timer Calculator
Astable & monostable mode timing
SoonBJT Transistor Bias Calculator
Compute Q-point and bias resistors
SoonMOSFET Drive Calculator
Gate drive and switching loss reference
SoonZener Diode Reference
Zener selection, voltage and current ratings
SoonLED Driver Calculator
Series resistor and current for LEDs
SoonVoltage Regulator Reference
Linear & switching regulator topologies
SoonADC/DAC Resolution Calculator
Bit resolution, LSB and SNR
SoonSampling Rate Calculator
Nyquist rate and sampling intervals
SoonSignal Integrity Reference
Impedance, reflections and ringing
SoonEMI/EMC Checklist
Common EMI/EMC compliance checks
SoonESD Protection Reference
ESD device classes and protection
Mechanical Engineering
Stress, strain, beams, gears & machine design
Stress & Strain Calculator
Axial stress, strain and modulus
SoonFactor of Safety Calculator
Allowable vs. applied stress ratio
SoonBeam Deflection Calculator
Deflection formulas for common beams
SoonColumn Buckling Calculator
Euler critical load for columns
SoonShaft Torsion Calculator
Shear stress and angle of twist
SoonBearing Life Calculator (L10)
L10 life from load and rating
SoonGear Design Reference
Module, pitch, ratio and forces
SoonMaterial Properties Comparator
Compare metals, alloys, polymers
SoonHeat Transfer Calculator
Conduction & convection rates
SoonFluid Pressure Calculator
Pressure from depth and density
SoonPressure Vessel Reference
ASME design stress references
SoonFastener Torque Reference
Torque values for bolt sizes & grades
SoonSurface Finish Ra Reference
Ra ranges by manufacturing process
SoonTolerance Stack Calculator
Worst-case & RSS tolerance stack
SoonFailure Mode Reference (FMEA)
Common failure modes & severity
SoonReliability Calculation Reference
MTBF, MTTF and reliability formulas
Civil & Structural
Beams, concrete, steel sections & loads
Beam Bending Moment Calculator
Bending moment for common loadings
SoonShear Force Diagram Builder
Plot shear & moment along a beam
SoonConcrete Mix Design Reference
Mix ratios and strength classes
SoonSteel Section Properties Table
I, S, Z for standard steel sections
SoonLoad Combination Reference
ASCE/IBC load combinations
SoonSoil Bearing Capacity Reference
Allowable bearing by soil type
SoonPile Load Calculator
End bearing & friction capacity
SoonDrainage Slope Calculator
Slope from rise and run
SoonConcrete Volume Estimator
Cubic volume for slabs, footings, columns
SoonMasonry Wall Design Reference
Allowable stresses & reinforcement
SoonBridge Deck Load Reference
HS-20, HL-93 and similar loads
SoonTraffic Load Reference
Vehicle load classes and impact
Chemical Engineering
Reactions, balances, flow & gas laws
Stoichiometry Calculator
Balance and quantify reactions
SoonMolar Mass Calculator
Molar mass from formula
SoonReaction Yield Calculator
Theoretical, actual and percent yield
SoonMass & Energy Balance Tool
Steady-state mass and energy balance
SoonDistillation Concept Tool
McCabe-Thiele concept & stages
SoonHeat Exchanger Reference
LMTD, NTU and effectiveness
SoonMixing Tank Volume Calculator
Cylindrical & conical tank volume
SoonViscosity Temperature Reference
Viscosity vs. temperature for fluids
SoonReynolds Number Calculator
Laminar/turbulent flow regime
SoonBernoulli's Equation Tool
Pressure, velocity & elevation head
SoonPhase Diagram Reference
P-T diagrams for common substances
SoonIdeal Gas Law Calculator
PV = nRT solver
Thermodynamics & Heat Transfer
Heat, cycles, insulation & thermal references
Thermal Conductivity Reference
k-values for common materials
SoonConvection Coefficient Calculator
h for natural & forced convection
SoonRadiation Heat Transfer Calculator
Stefan-Boltzmann radiation
SoonThermal Expansion Calculator
Linear & volumetric expansion
SoonSpecific Heat Capacity Reference
Cp values for materials
SoonRankine Cycle Visualizer
Steam power cycle T-s diagram
SoonBrayton Cycle Reference
Gas turbine cycle reference
SoonRefrigeration COP Calculator
Coefficient of performance
SoonInsulation R-Value Calculator
R-value from k and thickness
SoonHeat Load Estimator
Sensible & latent load estimate
Fluid Mechanics
Flow, pressure, pumps & pipe calculations
Flow Rate Calculator
Volumetric and mass flow rate
SoonPipe Head Loss Calculator
Friction head loss in pipes
SoonPump Power Calculator
Hydraulic and shaft power
SoonBernoulli's Principle Tool
Energy equation along a streamline
SoonDarcy-Weisbach Calculator
Friction factor head loss
SoonMoody Diagram Explorer
f vs Re for pipe roughness
SoonOrifice Plate Flow Calculator
Differential pressure flow measurement
SoonVenturi Flow Calculator
Flow from venturi pressure drop
SoonCompressible Flow Reference
Isentropic & shock relations
SoonHydrostatic Pressure Calculator
Pressure with depth
Control Systems
PID, transfer functions, Bode & stability
PID Controller Tuner (simulation)
Tune Kp, Ki, Kd interactively
SoonTransfer Function Explorer
Build and analyze transfer functions
SoonBode Plot Visualizer
Magnitude & phase plots
SoonNyquist Plot Reference
Nyquist stability criterion
SoonRoot Locus Concept Tool
Root locus shapes and rules
SoonStep Response Simulator
Time-domain step response
SoonFeedback Control Concept Builder
Build closed-loop diagrams
SoonControl System Stability Checker
Routh-Hurwitz stability test
Signal Processing
FFT, filters, sampling & modulation
FFT Visualizer
Frequency spectrum of a signal
SoonFourier Series Builder
Reconstruct waveforms from harmonics
SoonSampling Theorem Demonstrator
Aliasing & Nyquist demo
SoonFilter Design Reference
Butterworth, Chebyshev, Bessel
SoonDigital Filter Visualizer
FIR/IIR response plotter
SoonNoise Power Spectral Density Reference
PSD types and units
SoonConvolution Concept Tool
Visualize signal convolution
SoonAutocorrelation Visualizer
Autocorrelation of common signals
SoonSignal Modulation Reference
AM, FM, PM, QAM references
SoonNyquist Rate Calculator
Minimum sampling rate for a signal
Environmental Engineering
Carbon, water, air & green compliance
Carbon Footprint Estimator (basic)
Estimate basic CO₂e emissions
SoonWastewater Treatment Reference
Treatment stages and parameters
SoonAir Quality Index Calculator
AQI from pollutant concentration
SoonNoise Level Reference
dB levels of common sources
SoonWater Quality Parameter Reference
pH, BOD, COD, TDS ranges
SoonStormwater Runoff Estimator
Rational method runoff
SoonSoil Contamination Reference
Common contaminants & thresholds
SoonRenewable Energy Sizing Tool
Solar/wind sizing basics
SoonEnvironmental Impact Checklist
EIA project checklist
SoonGreen Building Compliance Reference
LEED & similar criteria
Manufacturing & Process
Lean, OEE, Six Sigma & SPC tools
Cycle Time Calculator
Production cycle time
SoonTakt Time Calculator
Demand-paced takt time
SoonOverall Equipment Effectiveness (OEE) Calculator
OEE = A × P × Q
SoonLean Waste Identification Tool
Identify 8 wastes of lean
SoonSix Sigma DPMO Calculator
Defects per million opportunities
SoonControl Chart Builder (SPC)
X-bar & R control charts
SoonProcess Capability Calculator (Cp, Cpk)
Capability indices
SoonKaizen Event Planner
Plan a kaizen event
SoonPFMEA Template
Process FMEA worksheet
SoonRoot Cause Analysis Tool (Fishbone/5-Whys)
Ishikawa & 5-Whys helper
Engineering Standards Reference
Units, ANSI, ISO, thread & symbol references
Unit Conversion Reference
Convert SI and imperial units
SoonSI Unit Reference
Base & derived SI units
SoonANSI Standard Reference
Common ANSI standards index
SoonISO Standard Reference
Common ISO standards index
SoonEngineering Material Database
Common engineering materials
SoonScrew Thread Reference
Metric & UN thread tables
SoonTolerance Grade Reference
IT grades and fits
SoonWeld Symbol Reference
AWS weld symbols
SoonNDT Method Reference
UT, RT, MT, PT, ET overview
SoonSafety Factor Reference
Typical safety factors by domain
SoonMaterial Hardness Scale Reference
Brinell, Rockwell, Vickers
SoonEngineering Drawing Symbol Reference
GD&T & drawing symbols