Harbour tide intelligence

Know the water before you leave the quay.

Tidemark turns harbour gauge readings into plain, hour-by-hour forecasts for small ports, marinas and working crews.

See a sample forecast

Sample station, next 24 hours

Illustrative data · metres above chart datum
High 4.2 m High 4.0 m Low 0.9 m Low 1.1 m 00:0006:0012:0018:0024:00
Next high water
04:10
Tidal range
3.3 m
Update cycle
15 min
Forecast horizon
7 days

Built for the waterfront

Forecasts a harbour master can read in ten seconds.

01

Local by design

Each forecast is tuned to a single gauge, so it reflects the shape of your harbour rather than a regional average.

02

Depth, not jargon

Enter a vessel's draught and see the safe windows for arrival and departure, marked clearly on the day's curve.

03

Works offline

Daily tide tables are ready to print or save, so the numbers stay with the crew when the signal drops.

How it works

From gauge to quay, every fifteen minutes.

  1. ReadGauge readings arrive and are checked against recent values.
  2. ModelHarmonic predictions are corrected for the current surge.
  3. PublishA fresh forecast and tide table are published for the station.
  4. ActCrews plan departures around clear, dependable windows.

Currently in private pilot.

Tidemark is being tested with a small group of harbours. New stations will open once the pilot is complete.