Tidebook: NOAA Tide Charts

The tide, worked out inside your iPhone — no signal needed, any date. All 3,489 NOAA stations, no ads, and one payment for Pro instead of a subscription.

Tidebook calculates the tide inside your iPhone.

Not a download. Not a cache. Tidebook carries NOAA's harmonic constants for 3,489 stations and works out the tide right on your phone — with no signal, on the boat, on the flats, for any date you ask for.

WHAT YOU GET FREE, FOREVER · 3,489 NOAA tide stations: every U.S. coast and territory, plus 28 abroad · The tide curve for today and the next seven days · Drag the curve to read the water at any hour — not just at high and low · Find your station by GPS, with the distance in plain sight, and a map to correct it in two taps · All the places you want, saved and side by side · Times in the STATION's time zone, labelled, with daylight saving handled · Sunrise, sunset, moonrise, moonset and the moon phase · Feet or metres · 12 or 24 hour · English and Spanish · dark mode

NO ADS. EVER. Not on the free side either.

TIDEBOOK PRO — ONE PAYMENT, YOURS FOR LIFE · Any month of any year, not just the next seven days · Tide alerts, including negative tides — the ones you want for clamming · Solunar fishing times · "Can I pass?" — put your draft on the chart and see the windows · Live sensor level vs. the table, at 238 NOAA stations — see what wind and weather are doing to the water right now · Conditions right now: wind, gusts, waves, water and air temperature and pressure from the nearest NOAA sensors and buoys · Share and print the day · Apple Watch, Lock Screen widget and a Dynamic Island countdown to the next tide

One payment. No subscription. We will never charge you again.

WHY THE NUMBERS ARE RIGHT Tidebook shows where each number comes from: the NOAA station, its distance, and for subordinate stations the reference station and the offsets applied. The engine is checked against NOAA's own published highs and lows, station by station.

Tide data from NOAA CO-OPS, public domain. Tidebook is not affiliated with NOAA. Predictions do not include wind, barometric pressure or river flow, which can change the real water level. Tidebook is a planning tool and does not replace a nautical chart.