EngineeringFormulaDisciplines
Every EngineeringFormula calculator, organized by engineering discipline. Jump straight to a tool, or browse the full calculator index.
Beams, walls, and sections - load, deflection, and material-quantity calculations for structural and site work.
- Board Foot CalculatorBF = T(in) × W(in) × L(ft) / 12
- Beam Deflection Calculatorδ = P L³ / (48 E I)
- Beam Reaction CalculatorRA = P(L − a)/L; RB = Pa/L
- Section Modulus CalculatorS = I / c
- Bending Stress Calculatorσ = M / S
- Area Moment of Inertia CalculatorIx = b h³ / 12; Iy = h b³ / 12
- Column Slenderness Ratio Calculatorλ = KL / r
- Retaining Wall CalculatorRows = ⌈H / h⌉
- Deck CalculatorRows = ⌈(W + g) / (bw + g)⌉
- Rafter Length CalculatorL = (R + O − t/2) × √(1 + (r/R)²)
- Fence CalculatorSections = ⌈L / s⌉
- Tile CalculatorColumns = ⌈(L + g) / (tl + g)⌉
- Siding CalculatorGross Area = P × H + Ag
- Drywall CalculatorWall Area = P × H
- Paint CalculatorNet Area = (P × H) − Ao
- Stair CalculatorN = max(1, round(R / rh))
- Roof Pitch CalculatorSlope = r / R
- Roofing Shingle CalculatorPitch Factor = √(1 + (X/12)²)
- Gravel CalculatorVolume = L × Wd × D
- Paver CalculatorN = ⌈Columns × Rows × (1 + W%)⌉
- Concrete CalculatorVolume (rectangular) = L × Wd × D
- Concrete Mix Ratio CalculatorVolume with waste = Vw × (1 + W%)
- Rebar Weight CalculatorUnit weight = π × d² × ρ / 4
- Footing Size CalculatorAdjusted load = P × (1 + a)
- Steel Weight CalculatorWeight (round bar) = π × (D / 2)² × L × ρ
Statics and dynamics fundamentals - force, motion, energy, and momentum problems shared across every engineering discipline.
- Force CalculatorF = m a
- Net Force CalculatorFnet = ΣF
- Gravitational Force CalculatorF = G m1 m2 / r²
- Kinetic Energy CalculatorKE = 1/2 m v²
- Impact Force CalculatorFavg = (1/2 m v²) / d
- Spring Force CalculatorF = k x
- Centripetal Force CalculatorFc = m v² / r
- Potential Energy CalculatorPE = m g h
- Acceleration Calculatora = (v - u) / t
- Velocity Calculatorv = Δx / t
- Free Fall Calculatorh = 1/2 g t²
- Momentum Calculatorp = m × v
- Projectile Motion CalculatorT = 2 v₀ sin θ / g
- Terminal Velocity Calculatorv = √(2mg / (Cd ρ A))
Machine elements - torque, gearing, belts, pulleys, and material behavior under load.
- Torque CalculatorT = F × r
- Bolt Torque CalculatorT = K × D × F
- Weld Strength Calculatorte = 0.707 × s
- Shaft Diameter Calculatord = (16T / (pi tau_d))^(1/3)
- Bearing Load CalculatorP = max(Fr, XFr + YFa)
- Torque Wrench CalculatorE_eff = E × cos θ
- Pulley Ratio Calculatori = D2 / D1
- Belt Speed Calculatorv = π × D × n
- Belt Length CalculatorL = 2sqrt(C² - e²) + d(π - 2β)/2 + D(π + 2β)/2
- Chain Length CalculatorL = 2C/p + (N1 + N2)/2 + (N2 - N1)^2 / (4pi^2 C/p)
- Sprocket Calculatori = N2 / N1
- Thread Pitch CalculatorPmm = 25.4 / TPI
- Spring Compression Calculatork = G d^4 / (8 D^3 Na)
- Flywheel Energy CalculatorE = 1/2 I omega^2
- Compression Ratio CalculatorCR = (Vs + Vc) / Vc
- Engine Displacement CalculatorV = n π B² S / 4
- Gear Ratio Calculatori = N2 / N1
- Horsepower CalculatorHP = P(W) / 745.7
- Stress Calculatorσ = F / A
- Strain Calculatorε = ΔL / L0
- Young's Modulus CalculatorE = σ / ε
Circuits and power - Ohm's law, AC/DC power, resistance networks, and battery and capacitor calculations.
- Ohm's Law CalculatorV = I × R
- Voltage Drop CalculatorVdrop = 2 × I × ρ × L / A
- Wire Gauge CalculatorRequired Ampacity = I × k, then select smallest gauge with Ampacity ≥ Required Ampacity
- Series & Parallel Resistance CalculatorRtotal = R1 + R2 + R3 + ...
- Electrical Power CalculatorP = V × I
- Voltage Divider CalculatorVout = Vin × R2 / (R1 + R2)
- Single-Phase Power CalculatorP = V × I × PF
- Three-Phase Power CalculatorP = √3 × VL × IL × PF
- Power Factor CalculatorPF = P / S
- Capacitor Energy CalculatorU = 1/2 C V²
- Battery Life Calculatort = C / I
- Amp Hour CalculatorAh = Wh / V
- Inductor CalculatorXL = 2 pi f L
- RC Time Constant Calculatorτ = R × C
- Watts to Amps CalculatorI = P / V
- kWh CalculatorDaily Energy = P × h / 1000
- Resistor Color Code CalculatorR = significant digits × multiplier
- LED Resistor CalculatorV_R = V_s − nV_f − V_driver
- Circuit Breaker Size CalculatorIreq = Inc + 1.25 × Ic, then choose the next standard breaker size ≥ Ireq
- Fuse Size CalculatorIreq = k × I, then choose the next standard fuse rating ≥ Ireq (k = 1.25 continuous, 1.0 intermittent)
- Diode CalculatorR = (V_s − V_F) / I
- Zener Diode CalculatorR_S ≤ (V_in,min − V_Z) / (I_L,max + I_Z,min)
- PCB Trace Width CalculatorW = [ I / (k ΔT^0.44) ]^(1/0.725) / t
Flow, pressure, and hydraulics - pipe flow, pump power, buoyancy, and the Bernoulli and continuity relations.
- Reynolds Number CalculatorRe = ρ v D / μ
- Bernoulli Equation Calculatorp1 = p2 + 1/2 ρ (v2² - v1²) + ρ g (z2 - z1)
- Hydrostatic Pressure Calculatorp = ρ g h
- Buoyant Force CalculatorF_B = rho g V_d
- Pump Hydraulic Power CalculatorP_h = rho g Q H
- Orifice Flow CalculatorQ = C_d A √(2 Delta p / rho)
- Venturi CalculatorQ = Cd A2 sqrt(2 Delta p / (rho (1 - beta^4)))
- Continuity Equation CalculatorA1 = A2 v2 / v1
- Flow Rate CalculatorQ = A v
- CFM CalculatorCFM = (W × H) v
- Duct Size CalculatorA = Q / v
- Pipe Size CalculatorA = Q / v
- Manning Equation CalculatorA = b × y
- Static Pressure CalculatorTESP = |Ps| + |Pr|
- Air Changes per Hour CalculatorV = L x W x H
- Water Pressure CalculatorP = ρ g h
- Pipe Volume CalculatorV = π d² L / 4
- Pressure Drop CalculatorΔp = f (L/D) (ρv²/2) + K (ρv²/2) + ρ g Δz
Heat and energy transfer - conduction, convection, ideal-gas behavior, and cycle efficiency.
- Carnot Efficiency Calculatorη = 1 − Tc / Th
- Convective Heat Transfer CalculatorQ̇ = h A ΔT
- Heat Energy CalculatorQ = m c ΔT
- Specific Heat Calculatorc = Q / (m ΔT)
- Heat Conduction CalculatorQ̇ = k A ΔT / L
- Thermal Conductivity Calculatork = Q̇ L / (A ΔT)
- Thermal Expansion CalculatorΔL = α L₀ (Tf − Ti)
- Ideal Gas Law CalculatorP = n R T / V
- Thermal Resistance CalculatorR = ΔT / Q̇
- U-Value CalculatorRlayer = L / k
- Heat Loss CalculatorQtrans = Σ(U × A × ΔT)
- HVAC Load CalculatorQenv = Σ(U × A × ΔT)
- Refrigerant Charge CalculatorLine charge = charged length delta × charge rate
- BTU CalculatorArea = L × Wd
- Dew Point Calculatorγ = (a × Tc) / (b + Tc) + ln(RH / 100)
- Wind Chill CalculatorWC = 35.74 + 0.6215T − 35.75V^0.16 + 0.4275T V^0.16