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Tide Calculator
Enter the day's HW/LW from your tide table — this interpolates the tide height at any time and finds your safe under-keel clearance window.
⚠ Interpolation aid only. Use official predictions (Admiralty TotalTide, NOAA, hydrographic office). This uses a smooth curve between HW/LW and ignores surge, meteorological effects and secondary-port corrections.
HW / LW events (from your tide table)
TypeTimeHeight (m)
Under-keel clearance requirement
Draft (m)
Required UKC (m)
Charted depth (m, chart datum)
Check a specific time
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