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From everyday measurements to advanced engineering units. Every conversion you need — length, weight, temperature, pressure, energy, and dozens more.
84+ Engineering Calculators
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Popular Conversions
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Core Units
Convert between kilometers, miles, feet, meters, inches, and more
72 conversionsConvert between kilograms, pounds, ounces, grams, and more
42 conversionsConvert between Celsius, Fahrenheit, Kelvin, and Rankine
12 conversionsConvert between mph, km/h, m/s, knots, and Mach
20 conversionsConvert between liters, gallons, milliliters, cups, and more
72 conversionsConvert between square feet, square meters, acres, hectares, and more
30 conversionsConvert between seconds, minutes, hours, days, weeks, and more
56 conversionsData & Technology
Convert between bytes, kilobytes, megabytes, gigabytes, and more
30 conversionsConvert between bps, Kbps, Mbps, and Gbps
12 conversionsConvert between HEX, RGB, HSL, and CMYK color formats
30 conversionsConvert between binary, octal, decimal, and hexadecimal
20 conversionsEncode and decode URL, HTML, Base64, and more
20 conversionsScience & Engineering
Convert between PSI, bar, atm, Pascal, and mmHg
132 conversionsConvert between joules, calories, kilowatt-hours, BTU, and more
42 conversionsConvert between watts, kilowatts, horsepower, and BTU/h
12 conversionsConvert between hertz, kilohertz, megahertz, and gigahertz
12 conversionsConvert between mpg, L/100km, and km/L
6 conversionsConvert between degrees, radians, gradians, and arc seconds
20 conversionsConvert between newtons, pound-force, kilogram-force, kips, and more
56 conversionsConvert between newton-meters, foot-pounds, inch-pounds, and more
42 conversionsConvert between m/s², ft/s², standard gravity, and more
20 conversionsConvert second moment of area between m⁴, cm⁴, mm⁴, in⁴, and ft⁴
20 conversionsConvert moment of inertia between kg·m², lb·ft², slug·ft², and more
30 conversionsConvert between rad/s, RPM, degrees per second, and revolutions per second
20 conversionsConvert between rad/s², deg/s², RPM/s, and rev/s²
12 conversionsConvert between kg/m³, g/cm³, lb/ft³, lb/in³, and more
56 conversionsConvert between Pa·s, centipoise, poise, and imperial viscosity units
30 conversionsConvert between m²/s, centistokes, stokes, ft²/s, and more
30 conversionsConvert between m³/s, GPM, CFM, L/min, and more
72 conversionsConvert between kg/s, lb/s, lb/hr, g/s, and metric ton per hour
42 conversionsConvert between N/m, mN/m, dyn/cm, lbf/ft, and lbf/in
20 conversionsConvert between J/(kg·K), kJ/(kg·K), BTU/(lb·°F), and cal/(g·°C)
20 conversionsConvert between W/(m·K), BTU/(hr·ft·°F), and cal/(s·cm·°C)
20 conversionsConvert between W/m², kW/m², BTU/(hr·ft²), and cal/(s·cm²)
20 conversionsConvert between W/(m²·K), BTU/(hr·ft²·°F), and kcal/(hr·m²·°C)
20 conversionsConvert between J/K, kJ/K, cal/K, and BTU/°R
12 conversionsConvert between J/(kg·K), kJ/(kg·K), BTU/(lb·°R), and cal/(g·°C)
12 conversionsConvert between J/kg, kJ/kg, BTU/lb, cal/g, and ft·lbf/lb
20 conversionsConvert between unitless strain, percent, microstrain, mm/mm, and in/in
20 conversionsConvert between N/m, N/mm, kN/m, lbf/in, and kgf/mm
20 conversionsConvert between kg/m, lb/ft, tex, denier, and more
30 conversionsConvert between μm, μin, nm, and mm roughness values
12 conversionsConvert between m/min, m/s, ft/min (SFM), and ft/s
12 conversionsEveryday
Convert cooking measurements with ingredient-specific accuracy
480 conversionsConvert shoe sizes between US, UK, EU, and CM systems
30 conversionsConvert clothing sizes between US, UK, EU, and Asian systems
20 conversionsConvert times between world timezones
2352 conversionsEngineering Classes
Calculators organized by university course — find every tool for your class.
Force systems, equilibrium, centroids, moments of inertia, friction, and trusses
Kinematics, kinetics, work-energy, impulse-momentum, and vibrations
Stress, strain, beam bending, torsion, column buckling, and combined loading
Ideal gas law, thermodynamic cycles, entropy, steam tables, and psychrometrics
Reynolds number, Bernoulli equation, pipe flow, pumps, open channel flow, and drag
Conduction, convection, radiation, heat exchangers, fins, and transient analysis
Shaft design, bearings, springs, fasteners, gears, welds, and fatigue analysis
Material properties, hardness conversion, thermal expansion, stress-strain analysis, and creep
Machining parameters, turning, drilling, tolerances, and surface finish
Interpolation, unit checking, significant figures, and reference tables
Transfer functions, Bode plots, root locus, PID control, stability analysis, state-space, and discrete-time systems
Normal distribution, hypothesis testing, regression, ANOVA, DOE, process capability, Weibull analysis
Free and forced vibration, isolation, critical speed, dynamic absorbers, FFT analysis, multi-DOF systems
Ohm's law, AC impedance, power calculations, RLC circuits, transformers, motors, and bridge circuits
Time value of money, NPV, IRR, depreciation, break-even analysis, loan amortization
Root finding, numerical integration, ODE solvers, curve fitting, matrix operations, interpolation
Uncertainty propagation, sensor calibration, strain gauges, thermocouples, signal analysis
Bubble/dew point, distillation, mass/energy balances, reaction kinetics, reactor sizing, packed beds, absorption columns, and vapor pressure
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All Unit Conversions
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Length & Distance(72 pairs)
Weight & Mass(42 pairs)
Speed(20 pairs)
Volume(72 pairs)
Area(30 pairs)
All Unit References
542+ unit education pages with conversion tables.