• Propane Tank Volume Calculator
    Calculate propane tank water capacity and usable gallons from diameter and length. Capsule-shape volume with adjustable fill percentage (default 80%).
  • Venturi Flow Rate Calculator
    Calculate volumetric flow rate, throat velocity and areas from a Venturi meter's pressure drop, diameters, fluid density and discharge coefficient.
  • Hagen-Poiseuille Pressure Drop Calculator
    Calculate the pressure drop of laminar fluid flow through a pipe using the Hagen-Poiseuille equation from viscosity, length, flow rate and diameter.
  • Partially Filled Circle Area Calculator
    Calculate the filled cross-section area and fill percentage of a partially filled circle or cylindrical tank from radius and fill depth.
  • Continuity Equation Flow Rate Calculator
    Solve the continuity equation A₁v₁ = Aā‚‚vā‚‚ for fluid velocity and find volumetric flow rate Q = AĀ·v in pipes and ducts instantly.
  • Pump Affinity Laws Calculator
    Use the pump affinity laws to find new flow, head, and power when impeller speed changes. Enter initial values and the new RPM to get instant results.
  • Rectangular Pool Volume Calculator
    Calculate how many gallons of water your rectangular pool holds. Enter length, width, and average depth in feet to get the volume instantly.
  • Dynamic to Kinematic Viscosity Calculator
    Convert dynamic (absolute) viscosity to kinematic viscosity with ν = μ/ρ. Enter μ in Pa·s and density ρ in kg/m³ to get ν in m²/s, cSt and St.
  • Milliliters to Fluid Ounces Converter
    Convert milliliters (mL) to US fluid ounces (fl oz) instantly. Enter a volume and get the precise fluid ounce result using floz = ml / 29.5735.
  • Antoine Equation Vapor Pressure Calculator
    Calculate vapor pressure from Antoine equation coefficients (A, B, C) and temperature. Get results in mmHg, atm, bar and kPa instantly.
  • Flow Velocity from GPM and Pipe Diameter Calculator
    Calculate water flow velocity (ft/s) from flow rate in GPM and inside pipe diameter in inches. Free pipe velocity calculator with formula and example.
  • Minor Head Loss Calculator
    Calculate minor (local) head loss in pipe fittings using hL = K·v²/(2g). Enter the loss coefficient K and flow velocity to get head loss in meters.
  • Keg Volume Calculator
    Find how many beers are in a keg. Enter keg size and serving ounces to get servings, gallons, fluid ounces, and liters instantly.
  • Barrel Volume Calculator
    Calculate the volume of a barrel, cask, or drum using the Kepler approximation. Enter height and the middle & end diameters to get liters and gallons.
  • Hydraulic Horsepower Calculator
    Calculate hydraulic horsepower (HHP) from flow rate in GPM and pressure in PSI using HHP = (Q Ɨ P) / 1714. Fast, free, accurate.
  • Pressure Head Calculator
    Calculate pressure head h = P/(ρg) in meters of fluid from pressure, density and gravity. Free online hydraulics & fluid mechanics tool.
  • Pipe Flow Rate from Diameter & Velocity Calculator
    Calculate volumetric water flow rate (Q) in a pipe from inner diameter and velocity. Get results in m³/s, L/s, and m³/h instantly.
  • Flow Rate Calculator (Volume Ć· Time)
    Calculate volumetric flow rate from volume and time with Q = V/t. Convert results to L/s, L/min, m³/h and GPM instantly. Free online flow rate calculator.
  • Gallons Per Hour (GPH) Calculator
    Calculate gallons per hour (GPH) flow rate from a volume in gallons and elapsed time in hours. Free, instant GPH and GPM results.
  • GPM to LPM Flow Rate Converter
    Convert flow rate from gallons per minute (GPM) to liters per minute (LPM) instantly. Also shows liters per hour and cubic meters per hour.
  • Pipe Cross-Sectional Area Calculator
    Calculate the internal cross-sectional area of a pipe from its inside diameter using A = Ļ€D²/4. Supports mm, cm, inches and meters.
  • Tap Water Cost Calculator
    Calculate the cost of tap water from the volume used and your price per liter. Estimate water bills, showers, baths, gardens and more instantly.
  • Friction Calculator
    Compute friction force from normal force and coefficient of friction. Enter normal force (N) and coefficient (μ) to get F = μN instantly in newtons.
  • Dynamic Pressure Calculator
    Calculate dynamic pressure q = ½ρv² from fluid density and flow velocity. Get instant results in pascals and kilopascals for aerodynamics and fluid flow.