Engineering Calculators for Pumps, Pipes, Motors and Treatment Plants
Free engineering calculators for pumps, pipes, motors, compressors, tanks, chemical dosing, and water and wastewater treatment.
51 free tools availableβ Top Picks in Engineering
Aeration Basin Volume Calculator
Preliminary aeration basin volume from F/M ratio biological design and hydraulic retention time (HRTβ¦
Use FreeBlower Capacity Calculator
Estimate wastewater blower shaft power, motor power, recommended IEC motor rating, and continuous enβ¦
Use FreeClarifier Area Calculator
Size clarifier surface area from peak flow and design overflow rate.β¦
Use FreeDecanter Centrifuge Calculator
Calculate decanter centrifuge G-force, bowl tip speed, sludge dry-solids loading, captured solids, cβ¦
Use FreeHydraulic Retention Time (HRT) Calculator
Calculate detention time from tank volume and flow, or size required volume for a target HRT.β¦
Use FreeOxygen Requirement Calculator
Estimate daily oxygen demand for carbonaceous BOD removal and optional nitrification.β¦
Use FreeAll Engineering Calculators
Aeration Basin Volume Calculator
Preliminary aeration basin volume from F/M ratio biological design and...
Use FreeAir Compressor Calculator
Calculate required air compressor shaft power and motor HP from FAD, i...
Use FreeAir Requirement Calculator
Convert daily oxygen demand to required dry-air flow in normal cubic m...
Use FreeBelt Filter Press Calculator
Estimate belt filter press throughput and polymer demand for sludge de...
Use FreeBlower Capacity Calculator
Estimate wastewater blower shaft power, motor power, recommended IEC m...
Use FreeBrick Calculator
Estimate bricks needed for a wall from area, brick rate, and waste all...
Use FreeCarbon Footprint Calculator
Estimate annual carbon footprint from driving, flights, home electrici...
Use FreeCement Calculator
Estimate cement bags for concrete volume using common mix ratios....
Use FreeChemical Dosing Calculator
Calculate chemical dosing rate in L/h and mL/min for water treatment. ...
Use FreeChlorine Dosing Calculator
Calculate chlorine mass and solution feed rate for disinfection....
Use FreeClarifier Area Calculator
Size clarifier surface area from peak flow and design overflow rate....
Use FreeClarifier Diameter Calculator
Convert required clarifier area to equivalent circular diameter....
Use FreeConstruction Cost Calculator
Estimate total construction cost for a residential building based on a...
Use FreeDecanter Centrifuge Calculator
Calculate decanter centrifuge G-force, bowl tip speed, sludge dry-soli...
Use FreeDiffuser Quantity Calculator
Estimate fine-bubble diffuser count from aeration floor area and spaci...
Use FreeEqualization Tank Volume Calculator
Estimate equalization basin volume from average flow, peak factor or m...
Use FreeF/M Ratio Calculator
Calculate food-to-microorganism ratio for activated sludge systems....
Use FreeFilter Press Calculator
Estimate filter press cake mass and cycle volume from batch feed....
Use FreeFlow Rate Calculator
Calculate the flow rate of liquids through pipes and channels. Convert...
Use FreeGravity Pipe Flow Calculator
Estimate full-pipe gravity flow with Manning's equation....
Use FreeHydraulic Loading Rate Calculator
Compute surface hydraulic loading rate for basins, ponds, and filters....
Use FreeHydraulic Retention Time (HRT) Calculator
Calculate detention time from tank volume and flow, or size required v...
Use FreeMLSS Calculator
Calculate mixed liquor suspended solids mass in the aeration basin....
Use FreeMLVSS Calculator
Estimate volatile suspended solids from MLSS and volatile fraction....
Use FreeMotor Power Calculator
Calculate motor mechanical power, horsepower, and estimated current fr...
Use FreeOxygen Requirement Calculator
Estimate daily oxygen demand for carbonaceous BOD removal and optional...
Use FreePaint Quantity Calculator
Estimate paint gallons from wall area, number of coats, paint coverage...
Use FreePipe Friction Loss Calculator
Estimate head loss in a straight pipe using the DarcyβWeisbach equat...
Use FreePipe Size Calculator
Calculate required pipe diameter for a given flow rate and velocity. R...
Use FreePipe Velocity Calculator
Calculate average pipe velocity from flow rate and internal diameter....
Use FreePipe Volume Calculator
Calculate the internal volume of a pipe based on its diameter and leng...
Use FreePolymer Consumption Calculator
Estimate daily polymer use from dry solids load and active dose....
Use FreePump Flow Calculator
Calculate pump flow rate from pump power, head, efficiency, and fluid ...
Use FreePump Horsepower Calculator
Calculate pump horsepower and required shaft power from flow rate, tot...
Use FreeRAS Flow Calculator
Estimate return activated sludge flow from clarifier underflow concent...
Use FreeSRT Calculator
Determine solids retention time from MLSS inventory and waste solids r...
Use FreeSVI Calculator
Compute sludge volume index from 30-minute settled volume and MLSS....
Use FreeScrew Press Calculator
Size screw press capacity from feed dry solids loading....
Use FreeSludge Volume Calculator
Calculate STP/ETP sludge dry mass in kg/day with and without chemical ...
Use FreeSodium Hypochlorite Dosing Calculator
Convert NaOCl solution strength to available chlorine feed rate....
Use FreeSurface Overflow Rate Calculator
Size clarifier area from flow and target surface overflow rate (SOR)....
Use FreeTank Capacity Calculator
Calculate tank capacity for rectangular, cylindrical, or conical tanks...
Use FreeTank Volume Calculator
Calculate the storage capacity of various tank shapes including rectan...
Use FreeThickener Calculator
Size gravity thickener area from solids loading rate....
Use FreeTile Calculator
Estimate tiles needed from surface area, tile size, and waste allowanc...
Use FreeTube Settler Calculator
Estimate projected settling area and module count for tube settlers....
Use FreeWAS Flow Calculator
Calculate waste activated sludge flow needed to maintain target SRT....
Use FreeWater Treatment Calculator
Estimate water treatment plant flow, coagulant and chlorine requiremen...
Use FreeWeir Loading Rate Calculator
Check clarifier weir loading from flow and total weir length....
Use FreeWind Chill / Heat Index Calculator
Calculate wind chill or heat index from temperature, wind speed, and h...
Use FreepH Correction Calculator
Estimate alkalinity supplement or acid dose for target pH movement....
Use FreeAbout Engineering Calculators
Use these free engineering calculators for preliminary mechanical and process design. Size pumps and pipes, estimate motor and compressor power, and check tanks, chemical feed, water treatment, and STP/ETP wastewater units with the governing formula shown on every page.
The mechanical tools cover fluid power (P = ΟgQH), pipe continuity and friction, tank geometry, motor output P = 2ΟNT/60, and single-stage isentropic air compression with k = 1.4.
Process and environmental tools cover chemical dosing, drinking-water treatment mass balances, and the full STP & ETP wastewater set: HRT, aeration, MLSS, SRT, clarifiers, sludge, and disinfection.
Results are planning estimates. Apply project-specific safety factors, vendor curves, and local codes before procurement or construction.