Fluid Mechanics Calculators
35 free online tools for flow rate, pressure, pipe sizing, viscosity, pumps, hydraulic systems, air flow, and fluid properties. Calculate common fluid mechanics values quickly with practical formulas.
Flow & Fluid Properties
Flow Rate Calculator
Calculate volumetric flow rate from velocity, area, or fluid volume over time.
CalculateMass Flow Rate Calculator
Determine fluid mass flow using density, velocity, and cross-sectional area.
CalculateViscosity Calculator
Calculate dynamic or kinematic viscosity from fluid properties and flow conditions.
CalculateFluid Volume Calculator
Estimate fluid volume for common tanks, pipes, and containers.
CalculateSpecific Gravity Calculator
Calculate specific gravity by comparing fluid density with a reference density.
CalculateRelative Density Calculator
Determine relative density for liquids and other fluid materials.
CalculateBuoyancy Force Calculator
Calculate upward buoyant force from displaced fluid volume and density.
CalculatePressure & Head
Hydrostatic Pressure Calculator
Calculate pressure produced by a fluid column at a given depth.
CalculatePressure Head Calculator
Convert fluid pressure into equivalent pressure head.
CalculateTotal Head Calculator
Calculate total hydraulic head from elevation, pressure, and velocity.
CalculateHead Loss Calculator
Estimate hydraulic head loss caused by friction and flow resistance.
CalculatePipeline Pressure Loss Calculator
Estimate pressure losses along pipelines and fluid transport systems.
CalculatePipe Flow & Sizing
Pipe Flow Rate Calculator
Calculate fluid flow through pipes from diameter and velocity.
CalculatePipe Velocity Calculator
Determine fluid velocity in a pipe from flow rate and diameter.
CalculatePipe Diameter Calculator
Estimate the required internal pipe diameter for a target flow rate.
CalculateMoody Diagram Calculator
Estimate Darcy friction factor from Reynolds number and roughness.
CalculatePipe Pressure Loss Calculator
Calculate pressure losses caused by friction along a pipe.
CalculatePipe Pressure Drop Calculator
Estimate pressure drop across a specified pipe length.
CalculatePipe Sizing Calculator
Determine an appropriate pipe size from target flow and velocity.
CalculatePipe Capacity Calculator
Calculate the internal fluid volume capacity of a pipe.
CalculatePipe Thickness Calculator
Estimate required wall thickness from pressure and pipe dimensions.
CalculatePipe Pressure Calculator
Calculate pressure conditions within common piping systems.
CalculateOrifices & Flow Coefficients
Pumps & Hydraulic Power
Pump Head Calculator
Calculate the hydraulic head produced or required by a pump.
CalculatePump Power Calculator
Calculate hydraulic or shaft power required for pumping.
CalculatePump Efficiency Calculator
Determine pump efficiency from hydraulic output and input power.
CalculatePump Sizing Calculator
Estimate pump requirements using target flow and system head.
CalculateHydraulic Pump Calculator
Calculate hydraulic pump flow, pressure, displacement, and power.
CalculateHydraulic Power Calculator
Calculate hydraulic power from pressure and flow rate.
CalculateNet Positive Suction Head Calculator
Estimate NPSH available or required for pump cavitation analysis.
CalculateFan Power Calculator
Calculate fan power from flow rate, pressure, and efficiency.
CalculateAir, Water & Compressible Flow
Frequently Asked Questions
Common questions about fluid flow, pressure, pipe sizing, pumps, and hydraulic calculations.
These tools cover flow rate, viscosity, pressure, pipe velocity, pipe sizing, friction losses, pump head, hydraulic power, air flow, water flow, and other common fluid mechanics calculations.
Volumetric flow rate describes the volume of fluid passing a point per unit time, while mass flow rate describes the mass passing that point per unit time. Density connects the two quantities.
Pipe pressure drop depends on factors such as pipe length, diameter, fluid density, velocity, viscosity, surface roughness, and fittings. Many engineering calculations use the Darcy-Weisbach relationship.
Pump head represents the energy a pump transfers to a fluid per unit weight. It is commonly expressed as a height of fluid, such as meters or feet of head.
Yes. The calculators in this collection are available as free online tools for education, engineering checks, system planning, and everyday calculations.