Match the test
Confirm the named method, specimen preparation, and whether the value describes film, formed material, or a complete package.
Packaging calculator
Barrier & film unit converter.
Convert the common metric and imperial units found on flexible-packaging data sheets. Keep the original test conditions with every converted value.
PROJECT FOCUSA unit conversion makes the numbers readable. It does not make different test conditions equivalent.
Use the data without losing its context
Convert the unit. Preserve the conditions.
Choose the measurement, enter the data-sheet value, and switch the direction when needed. The result restates the same measurement in another unit system. It does not predict shelf life or normalize a different laboratory test.
Read the Barrier & Shelf Life guide ↗CONVERTING
Oxygen transmission rate (OTR)
Resultcm³ / m² / day
This converts the area basis only. Keep any stated pressure basis, temperature, humidity, and test method with the result.
Before comparing two values
The unit is only one part of the result.
Match the conditions
Keep temperature, relative humidity, pressure or humidity gradient, and any conditioning history with the converted value.
Match the quantity
Do not treat transmission rate, permeance, and permeability as interchangeable. Thickness-normalized values are a different quantity.
Quick reference
Common flexible-packaging conversions.
OTR1 cc / 100 in² / day = 15.500031 cm³ / m² / day
WVTR / MVTR1 g / 100 in² / day = 15.500031 g / m² / day
Thickness1 mil = 25.4 µm
Temperature°C = (°F − 32) × 5/9
Common questions
What the conversion tells you and what it does not.
What is the conversion from cc per 100 square inches per day to cc per square meter per day?+
Multiply the imperial value by 15.500031. Cubic centimeters and cc are the same volume. The conversion changes the area basis from 100 square inches to one square meter.
Can converted OTR or WVTR values be compared directly?+
Only when the test method, temperature, relative-humidity conditions, pressure or humidity gradient, specimen preparation, and other stated conditions are also comparable.
Does this calculator convert transmission rate to permeability?+
No. Transmission rate, permeance, and permeability are different quantities. Thickness and pressure-normalized units must not be added or removed without the appropriate material and test information.
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