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Tidal Height — Rule of Twelfths

Estimate tidal height at any time between HW and LW using the rule of twelfths.

Capt. Rob StentVerified

MCA Yachtmaster Ocean, MNZ Coxswain (restricted)

Offshore sailing instructor and maritime educator with 30 years of blue-water passages. Author of coastal navigation guides for NZ waters.

High water height (m)

Low water height (m)

Tidal period (hrs)

Hours after high water

Enter values above to see your result

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