Ounce or Ounce Force per Square Inch is a low pressure unit which is part of the British and American system of units. 1 ounce per square inch equals 430.922 pascals.
The ozf/in² is used mostly for very low pressure rated equipment such as breather valves or controllers for LP natural gas appliances.
There are exactly 16 oz/in² in 1 psi which duplicates the relationship between pounds and ounces used to measure mass and weight.
To convert 1 oz/in² into other pressure units please use the list of conversion factors below.
Click on a pressure unit link to obtain the equivalent oz/in² conversion value.
To convert different different values of ozf/in² please use our on page pressure calculator.
See how oz/in² are derived from SI units and check whether a unit matches one of the versions of identifying oz/in2.
Featured low pressure measurement products
100 mbar pressure logger for monitoring natural gas pressures - Data-logger for connecting to a natural gas supply pipework which serves a number of boilers in a building.
DS210 Combined Low Pressure Switch, Indicator and Sensor - Low range three in one pressure switch, pressure indicator and pressure sensor for use on pneumatics and HVAC applications.
Conversion Factors
- 0.00430922 bar
- 0.0625 psi
- 4.30922 mbar
- 430.922 N/m²
- 430.922 Pa
- 4.30922 hPa
- 0.430922 kPa
- 0.000430922 MPa
- 0.00439418 kg/cm²
- 43.9418 mmH2O 4°C (39.2°F)
- 4.39418 cmH2O 4°C (39.2°F)
- 0.0439418 mH2O 4°C (39.2°F)
- 1.72999 inH2O 4°C (39.2°F)
- 0.144166 ftH2O 4°C (39.2°F)
- 3.23218 mmHg 0°C (32°F)
- 0.323218 cmHg 0°C (32°F)
- 0.127251 inHg 0°C (32°F)
- 3.23218 Torr
- 3232.18 mTorr
- 0.00425287 atm
- 0.00439418 at
- 4309.22 dyn/cm²
- 1 oz/in²
- 3232.18 µHg 0°C (32°F)
- 0.0000279018 tsi (uk, long)
- 0.00003125 tsi (usa, short)
- 0.0045 tsf (usa, short)
- 9 psf
- 4.39418 g/cm²
Please note that the conversion factors above are accurate to 6 significant figures.
Featured low pressure measurement products
DPS300 User Switchable Pressure Range, Volts or Current Output Low DP Sensor - The DPS 300 is a low range HVAC differential pressure sensor. The lowest possible pressure range is 0...100 pascals. 2 or 3 switchable pressure ranges, plus volts or current output are included with most standard configurations.
Differential pressure, temperature and humidity controller for multi-zone pharmaceutical cleanrooms - Solving the challenge of multi-zone cleanroom monitoring. See how individual room transmitters for air pressure, temperature, and humidity can be networked to a central controller, providing both local analogue signals for BMS control and a complete digital record for quality assurance.
Derivation
The calculation below shows how the pressure unit Ounce per Square Inch (oz/in²) is derived from SI Units.
Formula
- Pressure = Force / Area
- Force = Mass x Acceleration
- Acceleration = Distance / (Second x Second)
SI Units
- Mass: kilogram (kg)
- Length: metre (m)
- Time: second (s)
- Force: newton (N)
- Pressure: pascal (Pa)
Input Values
- 1 Ounce = 0.02834952313 kg
- 1 Inch = 0.0254 m
- 1 Square Inch = 0.0254 m x 0.0254 m = 0.00064516 m²
- Acceleration = Standard Gravity = 9.80665 m/s²
Calculation
- 1 Ounce Force = 0.02834952313 kg x 9.80665 m/s² = 0.278013851 N
- 1 oz/in² Pressure = 0.278013851 N / 0.00064516 m² = 430.9223309 Pa
Featured low pressure measurement products
Low Range DP Sensors - Low range differential pressure sensors for measuring very small pressure differences.
Low range vacuum pressure logger for 0 to -60 inH2O g - I am interested in monitoring vacuum on a pipeline in the field with a portable data logger.
Alternate Descriptions
These are the different versions used for identifying oz/in² that you may find elsewhere.
- Ounce per Square Inch
- Ounce Force per Square Inch
- Ounces per Square Inch
- Ounces Force per Square Inch
- oz/in²
- ozf/in²
- oz/in^2
- ozf/in^2
- oz/sq in
- ozf/sq in
Conversion Tables
Select a look up table for converting a pressure reading in ounces force per square inch to other measurement units.
- psi » 0.1 to 2000 oz/in² → 0.0625 to 125.000 psi
Featured low pressure measurement products
Measuring negative pressure in hospital construction zones with a low range differential pressure transducer - Low-range differential pressure transmitter provides the resolution needed to verify negative pressure in hospital construction vestibules, ensuring containment of dust and airborne contaminants.
DM01 Multi-Range High Accuracy Pressure Gauge - High precision digital pressure gauge with 0.1% full scale accuracy, exchangeable pressure range modules from 100 mbar (1.5 psi) up to 400 bar (6000 psi).
Glossary of Low Pressure technical terms
- g Effect
- inH2O – Inches of Water Column at 4 deg C Pressure Unit
- mmH2O – Millimetres of Water Column at 4 deg C Pressure Unit
- Pa – Pascal Pressure Unit

