The tides follow the moon, not the clock
According to the BSH, two high tides at one place are on average 12 hours and 25 minutes apart. This interval corresponds to half a mean lunar day, half the time until the moon is due south in the sky again.
Two tides therefore last 24 hours and 50 minutes on average, about 50 minutes longer than a calendar day. That is why high and low tide slip later from day to day.
About 50 minutes a day, but not always exactly
The 50 minutes are an average. Over half a month the shift varies: in some weeks it is only about 30 minutes a day, in others considerably more. In Cuxhaven, for example, high tides in the week from 11 October 2026 were at 02:13, 02:48, 03:19 and 03:49, each a good half hour later than the day before.
For precise planning, don’t extrapolate yourself; look up the times for the day in question. The tide calendar for each place on the tide map shows the high and low tides of the coming days side by side.
The place shifts the times too
The tidal wave comes from the Atlantic and reaches the places on the German North Sea coast one after another. The BSH gives an example: high tide occurs on Borkum about two hours earlier than in Cuxhaven. If you travel between the islands and the mainland or into an estuary, use the times for your destination.
Plan with the times for the specific day and place. As a rule of thumb, each tide comes a good half hour to almost an hour later than the day before.
See the tide for your placeFrequently asked questions
How much later does the flood come each day?
About 50 minutes on average, because two tides together last around 24 hours and 50 minutes. Depending on the week, the shift can be smaller or larger.
Are there two high tides every day?
On the North Sea coast usually yes. Because the times shift, a calendar day can also contain only one high or low tide when the second falls after midnight.