Beach

UV through the day#

Today’s estimated UV curve and forecast peak.

The white line is the UV index through the day, from an hour before dawn to an hour after dusk. It is estimated from how high the Sun is: at the day's highest point it equals the forecast UV for a clear sky, and it falls with the Sun's height, reaching 0 at the horizon. Clouds, haze, altitude, sand, water and snow change the real value; a forecast peak for the actual sky is in Sun and sky now.

The colour under the line is the UV category at each moment. Dashed lines mark UV 2, 6 and 8. The golden bar under the horizon line marks the tanning windows. The big figure is the UV now, with the category it falls in and when that ends.

When today's forecast can't be loaded, UV estimates, the curve and exposure windows are unavailable.

Sun and sky now#

Current sky conditions and UV.

Cloud cover now, as a share of the sky, and three UV figures: the estimate for this moment from the curve, the forecast highest UV today with the expected clouds, and the highest UV today if the sky were clear. Thin or broken cloud lets most UV through, so a cloudy day can still burn.

Tanning windows#

Today’s UV windows and countdowns.

Stretches of today when the estimated UV is between 2 and 6, worked out in ten-minute steps from civil dawn to dusk. The heading counts down to the end of the window you are in, or to the start of the next one. Each window is listed with its times.

Sunset#

Sunset time and direction.

Today's sunset with a countdown, sunrise, and the hours of daylight between them. Sunrise and sunset are when the Sun's upper edge meets a flat horizon; cliffs or buildings bring them closer to midday.

Sunscreen reminders#

Track applications and schedule reminders.

Choose your planned stay and start the beach session to set your departure time. This does not record sunscreen use. After applying sunscreen, tap Applied sunscreen now to record the actual application and schedule local reapplication alerts every two hours until departure. Tap Reapplied now after each application to reset the timer without extending your stay. End beach session cancels this feature's pending alerts. Sessions and timers survive closing and reopening the app.

After recording an application, the ring and minutes countdown track the next reapplication or departure, whichever comes first; a full red ring means reapplication is due. The timer uses real time, independently of the Sun-path slider. If you plan to leave before the next two-hour mark, no reapplication alert is scheduled for that period. This does not mean you can skip reapplying after swimming, sweating or towelling.

Notifications need permission; if permission is denied the in-app timer remains available, with a Settings link. Focus and system settings can silence or delay alerts. Neither UV nor SPF extends the two-hour interval, and the app does not calculate a safe tanning duration. Follow your sunscreen label. American Academy of Dermatology guidance recommends broad-spectrum, water-resistant SPF 30+ and reapplication at least every two hours outdoors, or sooner after swimming or sweating.

Parasol shade#

Estimate the shade from a canopy.

This live top view uses the current Sun position, independently of the Sun path planning slider. Hold your phone flat with its top pointing ahead: the diagram rotates with the true-north compass. N marks north and the gold Sun marks the live Sun bearing. Without a valid true-north reading, the diagram explicitly falls back to north-up. The dashed gold circle is the canopy directly over its pole; the solid teal circle is its projected shade on the sand. Enter the height of the canopy plane and its diameter. The white point is the pole. The drawing rescales to fit both circles; the scale bar shows ground distance.

For an ideal flat, horizontal circular canopy over level ground, the shade is a circle of the same diameter, displaced opposite the Sun by height ÷ tan(Sun altitude). Area is π × radius². The pole is shaded when that displacement is no greater than the canopy radius. A real domed or tilted parasol, slopes, nearby obstacles and diffuse light change the footprint. Below the horizon there is no direct-Sun shade; near the horizon the offset becomes very large.

The footprint describes direct sunlight, not UV protection. Reflected and scattered UV can reach you under a parasol; use protective clothing and sunscreen as well.

Full-day Sun path#

Explore the Sun’s bearing and altitude.

The chart follows the Sun's altitude from local midnight to the next midnight. Gold is above the geometric horizon; teal is below it. The horizontal zero line is the horizon, and the dashed vertical line marks the chosen minute. Move the slider to explore today or tap Now to follow the current time. Bearings run clockwise from true north: east 90°, south 180°, west 270°.

The curve is sampled every ten minutes; the selected numeric bearing and altitude are calculated at that exact minute. Times are the chosen place's local time and include daylight-saving changes. This is the Sun's geometric centre, so it can still be slightly below 0° at visible sunrise because of refraction and the Sun's size.

Live shadow#

The shadow direction and length now.

Where shadows fall right now and how long they are. The ring turns with your phone's compass: the mark at the top is the way the phone points, N is north, the golden dot the Sun's direction and the teal arrow the shadow, always opposite the Sun. The arrow is longer when the Sun is lower.

Set the height of the object (a person, a windbreak, a parasol up to 2.5 m) to see its shadow's length: the height divided by the tangent of the Sun's height. Below 45° shadows are longer than the object is tall; above 45° shorter. Low Sun gives very long shadows, so anything over 50 m is shown as 50+.

Sun height is the angle above the horizon; Sun direction and Shadow points are compass bearings.