以下：up to

鋼板は2㎜以下の厚さを有する。

ChatGPT:

ChatGPT

The steel plate has a thickness of 2 mm or less.

あなた:

How about "The steel plate has a thickness up to 2 mm"?

ChatGPT:

ChatGPT

Yes, "The steel plate has a thickness up to 2 mm" is also a suitable translation. This phrasing is clear and accurately conveys the maximum thickness limit without altering the meaning. Both versions are correct, though "up to 2 mm" may sound slightly more natural in some contexts.

あなた:

Is "up to" inclusive?

ChatGPT:

ChatGPT

Yes, "up to" is generally understood as inclusive, meaning it includes the specified upper limit—in this case, 2 mm. So, when you say "up to 2 mm," it includes thicknesses of exactly 2 mm as well as any value below that.

This aligns with the intent of the original Japanese phrase (2㎜以下), which is inclusive of 2 mm.

あなた:

But some people say "up to and including", don't they?

ChatGPT:

ChatGPT

Yes, some people do say "up to and including" to emphasize inclusivity. While "up to" on its own is typically understood as inclusive, adding "and including" can make it unambiguous, especially in technical or legal contexts where precision is crucial.

In most cases, though, "up to" alone is sufficient to imply inclusivity, especially when the context or convention already assumes it. Using "up to and including" simply clarifies further if there's any doubt about the inclusivity of the upper limit.