About
Know before you go in.
Swimmable was born from a simple observation: we have live data for weather, traffic and almost everything else, but swimming conditions stay a mystery until you reach the water. We pull public data from sources like NOAA, Open-Meteo, the European Environment Agency and the U.S. EPA and turn it into one Swim Score out of 10, so you can make a more informed choice about when and where to swim.
Swimmable is made by the founder of SwimPass. It is built for swimmers first: calm about risk, precise about data, and honest when we don't know.
How the Swim Score works
- Rules, not a black box: water temperature, air temperature, UV, wind and weather, waves and alerts each get a 0-10 factor score, weighted into one number.
- The weakest factor limits the total, so one bad reading (a storm, big surf) can't be averaged away.
- Missing data is left out and shown as missing. Without a water temperature, the score is capped at Fair.
- Bands: Poor under 4, Fair 4-6.9, Good 7-8.4, Glass 8.5 and up. The word always sits next to the colour.
- Official water-quality classifications (EU) are shown next to the score. They describe past seasons of sampling, not today's water.
Conditions change fast. Scores summarise public data and can be wrong or out of date; they are not a safety guarantee. Always follow lifeguards and posted signs.
Data sources
- NOAA CO-OPSMeasured water temperature at tide stations (U.S.).
- NOAA NDBCBuoy water temperature and wave height, used directly or as a cross-check.
- Open-MeteoAir temperature, wind, UV, precipitation, thunderstorm signals and the hourly forecast (model data).
- Open-Meteo MarineModelled wave height, period and sea-surface temperature where no station is close.
- OpenWeather, OpenUVCurrent weather, alerts and UV where configured.
- European Environment AgencyThe EU bathing-water register and annual quality classifications (CC BY 4.0).
- U.S. EPA BEACONLocations of beaches monitored under the BEACH Act (public domain).
- OpenStreetMapMap data, served as vector tiles by OpenFreeMap.
Get in touch
Questions about your data: privacy@swimmable.app. Legal matters: legal@swimmable.app. Building something? See the API.