Metric is a centrally planned system where everything is measured in an intuitive base-10 way.

Imperial is a hodgepodge of pre-1900's units of measurements from throughout history with absolutely no consistency or reason to it.

Because the Metric system is based on water, and the Imperial system is based on hacked together bullshit from a dozen different measuring systems combined.

A gram is a Metric unit, the mass of 1 ml of water. A pound is an Imperial unit loosely based on the ancient Roman libra, the mass of...nothing in particular, that we are aware of.

The reason for the inconsistency is you are assuming 1 fluid ounce of water weighs 1 ounce, and thus that 1 pint of water weighs 1 pound.

But once again the US unit system is letting you down with its lack of consistency. 1 fluid ounce of water weighs more like 1.04 ounces.

Well fuck, honestly I always thought fluid ounces and dry ounces were equal with water. I didn’t even look it up to check.

Imperial measurements are old, and don't get updated or defined constantly the way metric has to be for scientific purposes. This means many of the unit conversions are only approximate, and may not hold for all versions of the system.

A US (fl) oz of water is actually equivalent to 1.043 US dry ounces. Correcting for that should make up for the difference you're seeing.

https://en.wikipedia.org/wiki/Fluid_ounce

> An imperial fluid ounce is 1⁄20 of an imperial pint, 1⁄160 of an imperial gallon or exactly 28.4130625 mL.

> A US customary fluid ounce is 1⁄16 of a US liquid pint and 1⁄128 of a US liquid gallon or exactly 29.5735295625 mL, making it about 4.08% larger than the imperial fluid ounce.

> A US food labeling fluid ounce is exactly 30 mL.

Seems like the fluid ounce is just a shit show in general.

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