Tide Calculator

Tides shift throughout the day and vary by location — the Tide Calculator forecasts high and low tide times and heights for any coastal city, harbor, or port. Enter your location, a start date, and up to 30 days to forecast to see your next high tide, next low tide, tidal range, and current moon phase. Select your preferred time format and height unit (feet or meters) to match your needs.

Enter a coastal city, harbor, or port name

Number of days to show tide predictions

Results

Next High Tide

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High Tide Time

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Next Low Tide

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Low Tide Time

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Tidal Range

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Moon Phase

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Results Table

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Frequently Asked Questions

How accurate are tide predictions?

Tide predictions are typically accurate within 15 minutes for timing and within 0.1 feet for height. Accuracy may vary based on local weather conditions and geographic factors.

What causes tides?

Tides are caused primarily by the gravitational pull of the moon and sun on Earth's oceans. The moon has the strongest influence due to its proximity to Earth.

What's the difference between high tide and low tide?

High tide occurs when water levels are at their highest point, while low tide is when water levels are at their lowest. Most locations experience two high tides and two low tides per day.

How does moon phase affect tides?

During new and full moons (spring tides), tidal ranges are larger with higher high tides and lower low tides. During quarter moons (neap tides), tidal ranges are smaller.

Can weather affect tide times?

While predicted tide times remain constant, weather conditions like strong winds, barometric pressure changes, and storms can affect actual water levels by several feet.

Why do some locations have only one tide per day?

Some locations, particularly in the Gulf of Mexico and parts of Southeast Asia, experience diurnal tides with only one high and one low tide per day due to their geographic position.

What is tidal range?

Tidal range is the difference in height between high tide and low tide. It varies by location and can range from less than a foot to over 50 feet in extreme locations like the Bay of Fundy.

How far in advance can tides be predicted?

Tides can be accurately predicted years in advance because they follow predictable astronomical cycles. However, most tide tables provide predictions for the current year.