I'm not certain, but I'm pretty sure it's sold per gram in the UK.

The American units sound very unfamiliar to most British people under about 40 years old. 3/8 oz?

Road speed is still given in miles per hour, but anything where fractions or calculation might get involved (cooking, measuring furniture, drinking spirits) is done using metric units.

In Northern Germany, it's definitely in grams. That much I know, considering half of my high school used to talk all day about that.

That used to be the case, but lately I learned the gram is becoming a common unit for weed - replacing the dime bag.

The eighth is still common, as in (1/8 of an ounce) but now measured as 3.5 grams.

It's a weird mix right now.

Well, 7g is about a quarter oz, so it's still imperial influenced at least.

And in the US, we often refer to imperial amounts by their gram amounts as well. Especially in legal states I feel. Usual amounts are 1 gram, 3.5, 7, 14 and so on, lining up with the old, small amount ("dime"), eighth, quarter, and half o.

In Germany, it's common to measure drugs of all kinds, including dope, in (kilo/milli) grams (kg if you're talking about some serious shit, mg for the synth stuff).

I think it's just in grams. You're "allowed" to carry 5 grams on you, so 7g wouldn't make sense.