18:00 - eighteen hundred ?

I believe eighteen hundred, or eighteen hundred hours is the correct use of the 24 hour clock.

Possibly, saying eighteen hundred hours is easier when you calculate elapsed time. If something starts at 10:00 a.m. and ends at 2:00 p.m. it can get confusing when you try to find how long it lasted. If you subtract 10 from 2, the answer is not only confusing, it isn't meaningful. If you use the 24 hour clock, you only have to subtract ten hundred hours from fourteen hundred hours. The answer is four hours. That is accurate and not confusing at all.

I hope the answer doesn't add to the confusion.

The common English usage would be "eighteen hundred," or "eighteen hundred hours."

Excellent, Roger!

Nobody says this in English speaking countries.

Thank you.

Thank you. Your answer is very helpful!