The length of an Ark day is 24 hours. This is the same length as one Earth day. The reason for this is because the Earth’s rotation on its axis takes 24 hours.
The ark day is divided into two 12 hour periods, with each period having 12 hours of light and 12 hours of darkness.
An Ark Day is a really long time! It’s so long, in fact, that it’s actually two days.
ARK Surviving SOLO On A Sky Base Day 1
How Many Days are in an Ark Year
There is no definitive answer to this question as it depends on which interpretation of the Bible you follow. Some people believe that the ark year was 360 days long, while others believe it was 365 days long. The most commonly accepted interpretation is that the ark year was 360 days long, made up of 12 months of 30 days each.
This interpretation is based on the fact that the ancient Sumerians, who were thought to have been the first civilization to use a calendar, also used a 360-day year.

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Conclusion
According to the Bible, Noah’s Ark was afloat for approximately one year before it came to rest on Mount Ararat. If we assume that the length of a day was the same as it is today, then that would mean that the ark was afloat for about 365 days.