Methodology

Every fact on the site has a source and a date next to it. This page says how each one is measured and what the thresholds are.

Beach Score

A 0 to 10 number computed from stored components: facilities within walking distance (parking, bathrooms, restaurants, lifeguards, up to 3 points), free entry (1), sunset over water (1), calm water (up to 2), warm water (up to 1), and clear water (up to 2, with a neutral 1 when no clarity source exists yet). Components are stored separately and combined at render time. Affiliate revenue is not an input and never will be.

Today's beach-day rating

A 0 to 100 number on each beach page computed from the day's Open-Meteo forecast and marine model: start at 100, subtract 0.6 per percentage point of rain chance, 1.5 per km/h of peak wind above 20 km/h, 40 per metre of peak wave height above 0.6 m, 15 when the day's high is under 18 C, and 10 when it is raining or thundering now. 75 and above reads as a good day, 50 to 74 fair, under 50 poor. The inputs are printed next to the number. It is refreshed hourly and never affects the Beach Score or any ranking.

Tides

High and low tide times on a beach page come from the NOAA CO-OPS tide-prediction station nearest the beach, matched by the worker when the station is within 40 km (25 mi) and named next to the times with its distance. A reference station on the open coast is preferred over a subordinate one or one up a river or behind a bridge, unless it is much farther. Predictions are in the station's local time with heights above mean lower low water (MLLW). Tide times drift along a coast, so a station 20 km away can be off by tens of minutes; the distance is shown so the reader can judge. Beaches outside United States waters, and lake and river beaches, show no tides.

What counts as a beach

OpenStreetMap tags a street-end walkover, a named stretch inside a longer beach, and a destination beach the same way, so every row is classified on each data pass. A name that is a street end or says access (7th Avenue North Beach, Public Beach Access 3), mapped as a point or a shape under 300 m, is an access point. A named beach whose whole shape lies inside another beach's outline of 2 km or more, at least three times as long, is a section of it. A generic name (the beach, shoreline, seawall) is shoreline. A beach whose point lies inside a zoo, theme park, water park, or aquarium mapped as an area is an attraction: sand, but not a shore. Everything else is a destination. The homepage, place lists, and feature lists rank destinations and sections. Access points and shoreline keep their pages, appear on the map of the beach they serve, and are listed on their place page under their own heading. A short curated file corrects the cases the rules get wrong, and the reason for each call is stored with the beach.

Where the beach is, and how far things are from it

A beach is a stretch of shore, so distances to parking, restrooms, food, and stays are measured to the nearest point of its extent, not to one pin. The extent is the beach's own OpenStreetMap outline when it is mapped as an area or line; failing that, an unnamed beach shape within 150 m of a beach mapped as a point; failing that, a 600 m stretch of the nearest shoreline centred on the point, which the map draws fainter and the page calls approximate. Access points are where footways, paths, steps, and boardwalks in OpenStreetMap end within 30 m of the extent (60 m for a shoreline stretch), leaving out sidewalks, crossings, and private ways; endpoints within about 45 m of each other merge into one point, which keeps the nearest restrooms, showers, and parking within 200 to 250 m and is marked accessible when any of its paths is tagged for wheelchairs. Unnamed points are named by position: main, north, south. A beach shows up to 8.

Rip currents and beach alerts

The rip current risk, surf height, and thunderstorm potential on a beach page come from the National Weather Service Surf Zone Forecast for the beach's public forecast zone, issued by the local office once or twice a day and read at render time (cached 15 minutes). The worker matches each US ocean beach to its zone by stepping inland from the shore until a land zone answers. Active Rip Current Statements, Beach Hazards Statements, surf advisories, coastal flood and tropical products, and heat advisories for the zone appear with the forecast. A low risk means rip currents are unlikely in open surf, not absent: they still form near piers, jetties, groins, and inlets. A forecast older than 30 hours is not shown. A moderate or high risk is named in the day's summary but does not change the beach-day rating. Beaches outside the United States show nothing here.

Visitor reports and lifeguard flags

Anyone at a beach can tap what they see: the lifeguard flag flying (green, yellow, red, double red, or none posted, meanings per the United States Lifesaving Association), whether the purple flag for dangerous marine life is up, and the water, crowd, and seaweed. No account; one report per kind per beach per address a day. A flag report is current for 6 hours and recent for 24; after that it counts only in summaries. When several current reports disagree, the most common colour is shown with the number that agree. A beach with no report of its own borrows one from a beach within 2 km on the same shore (shore direction within 90 degrees), or within 5 km when it has none in 24 hours, always named with its distance. Summaries count reported days, not reports: the last 30 days here and within 5 km, and by calendar month across years for the planner, which shows a month only after 30 reported days over at least 2 seasons. Reports are visitor-submitted and skew toward busy days.

Typical weather for a date, and storm passes

The plan-a-visit picker on each beach page blends the monthly means (sea temperature, daily high, rain days, wave height) of the month picked and its neighbour, as if each mean sat on the 15th, so the 3rd of a month leans toward the month before. Rain days become the chance of a rainy day by dividing by the days in the month. The words next to the numbers follow fixed bands: water is cold under 16 C (61 F), cool to 20 C (68 F), mild to 24 C (75 F), warm to 27 C (81 F), and very warm above; a daily high is cool under 18 C (64 F), mild to 24 C (75 F), warm to 29 C (84 F), and hot above; rain is rare under a 20 percent chance of a rainy day, some to 35 percent, and common above; waves are usually calm under 0.5 m (1.6 ft) mean daily maximum, moderate to 1 m (3.3 ft), and often rough above. The through-the-year grid uses the same bands in five steps, and "when to go" picks the month that scores best on warm water, few rainy days, calm water, and a comfortable high, plus the neighbouring months nearly as good. Storm passes come from the NOAA National Hurricane Center HURDAT2 best tracks: a storm counts when its track, at tropical storm strength or stronger, came within 100 km (62 mi) of the beach, and it is filed under the month of closest approach. The window starts in 1980. Season dates are the NHC's for the basin.

When a page is published

• A beach page is listed in search engines only when its completeness score reaches 55 of 100. Completeness counts the modules present: photo, attributes, score, visitor reports, monthly climate, shore direction, hours and fees, nearby beaches, and questions.
• A "beaches with X in Y" list exists only when at least 5 ranked beaches in Y have X. Below that, the same view is a filter on the place page and has no address of its own.
• A town-level list that would repeat 80 percent or more of its region's list is not published either. One page per answer.
• A place page is listed when it has at least 3 ranked beaches.
• Every map on the site sits next to the same beaches as plain text and links, so nothing depends on the map loading.

Data coverage

A feature gets a list only when a source measures it for enough beaches. 22 features have lists today. Waiting for a source: clear water, shade, sea glass, white sand, pink sand, black sand, green sand, swimming pigs, wild horses, seals and sea lions, flamingos, birdwatching, fires allowed, free entry, wheelchair access.

Attributes

Text on the site

Summaries and questions are generated from the structured facts on the page and nothing else. Each sentence has to map to a stored field, and any sentence that fails the site's style check is dropped rather than rewritten. Visitor reports are one-tap and anonymous, rate-limited per address, and shown with their counts.

Data licenses and refresh dates are on the data page.