Conversion Factor Overview
The exact relationship is:
1 ml/s = 219.6855 in³/h
To go from millilitres per second to cubic inches per hour, multiply the value in ml/s by 219.6855. To reverse the conversion, divide the value in in³/h by 219.6855.
Understanding the Units
Volume Flow Rate
Volume flow rate measures how much space a fluid occupies as it moves over time. It combines a volume unit (like millilitres or cubic inches) with a time unit (seconds, minutes, hours, etc.).
Millilitre per Second (ml/s)
A millilitre is one‑thousandth of a litre, equal to one cubic centimetre (1 cm³). When expressed per second, it tells you how many millilitres pass a point each second. This unit is common in laboratories, medical devices, and small‑scale fluid systems.
Cubic Inch per Hour (in³/h)
A cubic inch is the volume of a cube with 1‑inch edges. When expressed per hour, it indicates how many cubic inches flow past a point in one hour. This unit appears in HVAC specifications, automotive fuel‑flow charts, and some industrial equipment that uses the Imperial system.
How to Convert
The conversion rests on two facts:
- 1 ml = 0.0610237441 in³ (because 1 cm³ = 0.0610237441 in³).
- There are 3,600 seconds in an hour.
Combine them:
ml/s × 0.0610237441 in³/ml × 3,600 s/h = in³/h
Multiplying the constants gives the single factor 219.6855. So the conversion formula is:
in³/h = ml/s × 219.6855
Worked Example
Suppose a medical infusion pump delivers 3 ml/s. How many cubic inches per hour is that?
Apply the factor:
3 ml/s × 219.6855 = 659.0565 in³/h.
Rounded to four decimal places, the pump’s flow rate is 659.0565 in³/h. This quick calculation helps engineers compare equipment that uses different unit systems.
Practical Applications
- Laboratory research: Convert small‑scale liquid delivery rates to match equipment specifications that list flow in Imperial units.
- HVAC design: Duct airflow may be measured in litres per second, but older manuals sometimes use cubic inches per hour for fan curves.
- Automotive fuel systems: Fuel injectors are rated in millilitres per second, while some performance charts use cubic inches per hour for historical reasons.
- Medical devices: Infusion pumps calibrated in ml/s can be cross‑checked against legacy documentation that references in³/h.
Millilitre per Second to Cubic Inch per Hour Conversion Table
Each row applies the same rule: multiply millilitres per second by 219.6855 to obtain cubic inches per hour (values rounded to 4 decimal places).
| Millilitre per Second (ml/s) | Cubic Inch per Hour (in³/h) |
|---|---|
| 1 ml/s | 219.6855 in³/h |
| 2 ml/s | 439.3710 in³/h |
| 5 ml/s | 1,098.4275 in³/h |
| 10 ml/s | 2,196.8550 in³/h |
| 20 ml/s | 4,393.7100 in³/h |
| 50 ml/s | 10,984.2750 in³/h |
| 100 ml/s | 21,968.5500 in³/h |
| 500 ml/s | 109,842.7500 in³/h |
Key Takeaway
Remember the single conversion factor: 1 ml/s = 219.6855 in³/h. With this number, you can instantly translate small‑scale metric flow rates into Imperial units and vice‑versa, keeping your projects on track regardless of the measurement system.
Need more conversions? Explore our suite of volume‑flow tools and make every calculation a breeze.