This fluid flow rate calculator can help you calculate the fluid flow rate, pipe diameter or the velocity in multiple measurement units if you know any 2 variables. Discover below the tool all the formulas applicable.

Instruction: Please input only 2 out of the 3 fields available to find the desired one!

Pipe diameter:*
Flow Rate:*

How does this fluid flow rate calculator work?

Depending on the variable to be computed this fluid flow rate calculator applies these formulas, while the user is requested each time to input 2 out of the 3 fields available (the unknown variable field should remain blank):

■ In case the pipe diameter (P) needs to be calculated the formula that is used is:

P = √(4F/πV)

■ When you want to solve for speed/velocity (V) the formula applicable is:

V = 4F/πP2

■ In order to calculate the flow rate (F) the following equation is suitable:

F = 1/4πP2V

Each of the three figures can be processed in different measurement units since this fluid flow rate calculator performs the conversion to the default unit by multiplying the value specified with one of the factors given in the tables below per each dimension:

■ Pipe diameter is by default set up to meters (m) thus from any other measurement unit it is converted to m by applying the following conversion rules:

From: To m:
m 1
cm 0.01
mm 0.001
ft 0.3048
in 0.0254
yd 0.9144

Speed/velocity is initially set up to meters per second (m/s) thus in the calculation phase any other unit selected is converted to m/s:

From: To m/s:
m/s 1
km/s 1000
km/min 16.66666667
km/h 0.277777778
m/min 0.016666667
m/h 0.000277778
cm/s 0.01
cm/min 0.000166667
cm/h 0.00000277778
mm/s 0.001
mm/min 0.0000166666667
mm/h 0.000000277778
mps (miles/s) 1609.344
mpm (miles/min) 26.8224
mph 0.44704
yd/s 0.9144
yd/min 0.01524
yd/h 0.000254
ft/s 0.3048
ft/min 0.00508
ft/h 0.00008466667
in/s 0.0254
in/min 0.000423333
in/h 0.00000705556

■ Flow rate is by default selected to be expressed in m3/s but in case other unit is chosen from the drop down list the calculator will convert it to m3/s:

From: To m3/s:
m3/s 1
m3/min 0.016666667
m3/h 0.000278
l/s 0.001
l/min 0.00001667
l/h 0.000000278
cm3/s 0.000001
cm3/min 0.000000017
cm3/h 0.000000000278
mm3/s 0.000000001000
mm3/min 0.0000000000166666667
mm3/h 0.000004
ft3/s 0.028316847
ft3/min 0.0004719474
ft3/h 0.000007865791
in3/s 0.00001639
in3/min 0.000000273117733
in3/h 0.000000004552
yd3/s 0.764554858
yd3/min 0.012742581
yd3/h 0.000212376
US gal/s 0.003785412
US gal/min 0.00006309
US gal/h 0.000001052

Within the results area, each variable calculated is displayed in all the measurements units available.

13 Aug, 2015