NOAA CO-OPS at https://api.tidesandcurrents.noaa.gov/api/prod/datagetter serves tide predictions and observed water levels for US stations. 9414290 is San Francisco.
None. Adding application= with your app's name is requested.
Full reference: https://api.tidesandcurrents.noaa.gov/api/prod/
curl "https://api.tidesandcurrents.noaa.gov/api/prod/datagetter?station=9414290&product=predictions&datum=MLLW&time_zone=lst_ldt&units=english&interval=hilo&format=json&date=today"{
"predictions": [
{
"t": "2026-09-23 03:54",
"v": "0.307",
"type": "L"
},
{
"t": "2026-09-23 10:49",
"v": "4.939",
"type": "H"
}
]
}curl "https://api.tidesandcurrents.noaa.gov/api/prod/datagetter?station=9414290&product=water_level&datum=MLLW&time_zone=gmt&units=metric&format=json&date=latest"{
"metadata": {
"id": "9414290",
"name": "San Francisco",
"lat": "37.8063",
"lon": "-122.4659"
},
"data": [
{
"t": "2026-09-23 21:36",
"v": "1.017",
"s": "0.061",
"f": "0,0,0,0",
"q": "p"
}
]
}