FWIW, bicycle chains are standardized around imperial (inch) standards, not metric. All derailleur chains have 1/2" pitch, and until you get to 10s chains, 3/32" nominal width, based on the sprockets they fit.
So, it's easier to work in inches, whereally, for example, the length in inches is equal to the the numple of full links (inner plus outer).
__________________
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.