Volumetric flow rate.
Cubic foot per Seconds to Cubic inch per Seconds Converter — ft3/s to in3/s
Convert Cubic foot per Seconds (ft3/s) to Cubic inch per Seconds (in3/s) using the exact conversion factor (1 cubic foot per seconds = 1,728 cubic inch per seconds). See the formula, worked examples, conversion table, and common uses.
Cubic foot per Seconds to Cubic inch per Seconds converter
Converter
Flow Rate Converter
Convert volumetric flow rates across metric, US, imperial, industrial, and scientific units.
Context values
Some unit families need one extra value for a physically accurate result.
Volumetric flow rate.
Result = input x 0.02831684659 / 1.6387064e-5.
Flow rate uses cubic meters per second as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Cubic foot per Seconds to Cubic inch per Seconds
Cubic foot per Seconds and Cubic inch per Seconds both measure volumetric flow rate — how much volume passes a point over time — used to size pipes and pumps, monitor river or stream discharge, control industrial processes, and set medical infusion rates. Cubic foot per Seconds is most often used for the standard unit used by the us geological survey for reporting river and stream discharge at gauging stations.
Formula
cubic inch per seconds = cubic foot per seconds × 1728
This factor comes from each unit's defined relationship to the category's base unit: 1 cubic foot per seconds equals 0.028316846592 base units, and 1 cubic inch per seconds equals 0.000016387064 base units, so dividing one by the other gives the direct cubic foot per seconds-to-cubic inch per seconds factor of 1728.
Simple example
1 ft3/s × 1728 = 1,728 in3/s
1 cubic foot per seconds = 1,728 cubic inch per seconds.
Real-world example
60 ft3/s × 1728 = 103,680 in3/s
60 cubic foot per seconds = 103,680 cubic inch per seconds.
Conversion table
| Cubic foot per Seconds (ft3/s) | Cubic inch per Seconds (in3/s) |
|---|---|
| 0.1 ft3/s | 172.8 in3/s |
| 1 ft3/s | 1,728 in3/s |
| 10 ft3/s | 17,280 in3/s |
| 60 ft3/s | 103,680 in3/s |
| 100 ft3/s | 172,800 in3/s |
| 1,000 ft3/s | 1,728,000 in3/s |
Reverse conversion: Cubic inch per Seconds to Cubic foot per Seconds
1 in3/s × 0.0005787037037 = 0.0005787037 ft3/s
1 cubic inch per seconds = 0.0005787037 cubic foot per seconds.
cubic foot per seconds = cubic inch per seconds × 0.000578703703704
For a page dedicated to this direction, see Cubic inch per Seconds to Cubic foot per Seconds.
Understanding the Cubic foot per Seconds
Cubic foot per Seconds (ft3/s) measures volumetric flow rate. One cubic foot of volume passing a point every second. It is classified as a US customary flow-rate unit.
Where it's used: United States
Uses of the Cubic foot per Seconds today
- The standard unit used by the US Geological Survey for reporting river and stream discharge at gauging stations
Understanding the Cubic inch per Seconds (in3/s)
Volumetric flow rate.
Cubic foot per Seconds — sources
- USGS Water Science School — Cubic feet per second (cfs) is the standard unit USGS uses to report streamflow.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many cubic inch per seconds are in 1 cubic foot per seconds?
1 cubic foot per seconds equals 1,728 cubic inch per seconds, using the exact defined conversion factor rather than an estimate.
How do I convert cubic foot per seconds to cubic inch per seconds?
Multiply the cubic foot per seconds value by 1728. The converter above does this instantly to whatever precision you set.
How do I convert cubic inch per seconds back to cubic foot per seconds?
Use the reverse factor: 1 cubic inch per seconds equals 0.0005787037 cubic foot per seconds. You can also use the swap control in the converter above to flip the direction instantly.
What is a cubic foot per seconds?
Cubic foot per Seconds (ft3/s) measures volumetric flow rate. One cubic foot of volume passing a point every second. It is classified as a US customary flow-rate unit.
What is a cubic inch per seconds?
Cubic inch per Seconds (in3/s) is a unit of flow rate.
Is the cubic foot per seconds to cubic inch per seconds conversion exact?
Yes. Both cubic foot per seconds and cubic inch per seconds are defined by fixed standards rather than physical artifacts, so the factor of 1728 used above is exact to as many digits as you choose to display.
Where is the cubic foot per seconds still used today?
United States
What's the difference between volumetric and mass flow rate?
Volumetric flow rate measures the volume of fluid passing a point per unit time (for example, liters per second). Mass flow rate measures the mass instead. For a fluid of constant density the two are directly proportional, but for compressible fluids like gases, mass flow is often the more meaningful quantity.