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.

## 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/πP ^{2}**

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

**F = 1/4πP ^{2}V**

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 m^{3}/s but in case other unit is chosen from the drop down list the calculator will convert it to m^{3}/s:

From: |
To m^{3}/s: |

m^{3}/s |
1 |

m^{3}/min |
0.016666667 |

m^{3}/h |
0.000278 |

l/s | 0.001 |

l/min | 0.00001667 |

l/h | 0.000000278 |

cm^{3}/s |
0.000001 |

cm^{3}/min |
0.000000017 |

cm^{3}/h |
0.000000000278 |

mm^{3}/s |
0.000000001000 |

mm^{3}/min |
0.0000000000166666667 |

mm^{3}/h |
0.000004 |

ft^{3}/s |
0.028316847 |

ft^{3}/min |
0.0004719474 |

ft^{3}/h |
0.000007865791 |

in^{3}/s |
0.00001639 |

in^{3}/min |
0.000000273117733 |

in^{3}/h |
0.000000004552 |

yd^{3}/s |
0.764554858 |

yd^{3}/min |
0.012742581 |

yd^{3}/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