Tides

What it shows

Sea level at the coast, hour by hour from yesterday to three days ahead: the astronomical tide, computed in your browser (the surge from wind and pressure is not included). Each dot is a port, coloured by where the water stands between its own low and high of the window and sized by its tidal range; a tap anywhere on the sea gives the level there, whether it is rising or falling, the curve and the times and heights of the day's high and low waters. Not for navigation: use the official tide tables of the port.

Where the data comes from

EOT20 global ocean tide model (DGFI-TUM, from multi-mission satellite altimetry, CC-BY 4.0): 9 harmonic constituents on a 0.25° grid, summed by your browser hour by hour from 24 h ago to 72 h ahead, no external call. High and low waters are interpolated between the hours.

Reading the map

Sand at the port's lowest water of the window, pale yellow, then teal at mid-tide and blue to deep blue at high water. Bigger dots have a bigger tidal range.

Units Metres above or below mean sea level; tidal range in metres; times in UTC.

Put this map on your site

Writing about it? Embed this live map: one iframe, free, no tracking, it stays up to date on its own.

Copy code

Other layers in sea

• Sea state
• Swell
• Ocean currents
• Sea surface
• Sea ice
• Ocean life