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Polythene thickness converter

Convert polythene thickness between micron, gauge, millimetres and mil. Type any value and the others update instantly.

100 gauge = 25 micron = 0.025 mm. 1 mil = 25.4 micron.

Micron, gauge, mm and mil explained

In the UK, polythene film, bags and sheeting are usually specified in microns (one thousandth of a millimetre). Gauge is an older measure still in common use, where 100 gauge equals 25 micron, so you multiply microns by four to get gauge. Mil is a US unit equal to 25.4 micron, and should not be confused with a millimetre.

MicronGaugemmMil
25 mu 100 0.025 0.98
50 mu 200 0.05 1.97
75 mu 300 0.075 2.95
100 mu 400 0.1 3.94
120 mu 480 0.12 4.72
150 mu 600 0.15 5.91
200 mu 800 0.2 7.87
250 mu 1000 0.25 9.84
300 mu 1200 0.3 11.81
500 mu 2000 0.5 19.69

Not sure which gauge suits your product? Try the bag size finder or ask us for a recommendation.

FAQ

Common questions

Quick answers on polythene thickness. Need a specific gauge made to size? We manufacture to your exact specification.

How do you convert micron to gauge?
Multiply microns by 4 to get gauge (100 gauge equals 25 micron). To go the other way, divide gauge by 4. For example, 50 micron is 200 gauge.
What is a micron?
A micron (also written as micrometre or mu) is one thousandth of a millimetre. Polythene film and bag thickness is usually specified in microns in the UK.
What is mil in plastic thickness?
Mil is a US unit equal to one thousandth of an inch, which is 25.4 micron. It is not the same as a millimetre, so it is worth converting before you order.

Need it made to your exact spec?

We manufacture tailor-made polythene packaging in Blackburn and deliver across the UK. Tell us your numbers and we will quote.

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