Sundial
A sun path app that runs in your browser
Looking for a sun path app to check where the sun will be over a house, a garden or a campsite? Sundial is a free web app: open it on your phone, search the place or use your location, and you'll see the sun's path over the real buildings around you. There's nothing to download.
Open the sun path appWhat it shows
Sundial is a 3D map. It draws the buildings near your chosen spot from OpenStreetMap, then puts the sun where it really is for that date and time. You get:
- The sun's arc across the sky for the chosen day, with the June and December solstice arcs and a compass for comparison.
- Real-time shadows from the surrounding buildings as you drag the date and time, or press play to run a day or a whole year.
- Sunrise, solar noon, sunset and day length, in the place's own time zone.
- Sun height and Sun bearing, so you know exactly which direction the sun is in and how high.
- A Sun hours heatmap that colours each patch of ground and roof by how many hours of direct sun it gets that day.
That makes it a sun tracker and a sun direction app at once, with the added picture of which surfaces the light actually reaches.
Add it to your home screen
Sundial has a web app manifest, so your phone can treat it like an installed app. It gets its own icon and opens full screen without the browser bars.
- iPhone or iPad (Safari): open sunpathmap.com, tap the Share button, then Add to Home Screen.
- Android (Chrome): open sunpathmap.com, tap the three-dot menu, then Add to Home screen or Install app.
Updates arrive by themselves, because each launch loads the current version from the web.
What it doesn't do
Sundial has no augmented-reality camera view, so you can't hold your phone up and see the sun's path drawn over the live picture. It doesn't read your phone's compass either. And it has no offline mode: it needs a connection to load map tiles and buildings, so it won't help on a hillside with no signal.
It also leaves out weather, cloud, terrain and the moon. The ground is treated as flat, so a valley or hillside will see the sun later or earlier than shown.
How it compares with installed sun tracker apps
Installed sun tracker apps from the app stores often focus on an AR overlay through the camera, offline use and alerts for sunrise or golden hour. Those are useful if you're standing in the spot and want to see the sun's line against the real view, or if you're working somewhere with no signal.
Sundial's strength is different. It's built around buildings and shadows: you can check a garden or a flat from your sofa, months ahead, and see which parts of it are in sun or shade at each hour. Sharing is a link, which opens the same place, date and time on anyone's phone or laptop without them installing anything. If you mostly plan from a desk, a browser tool covers it. If you need AR on location, an installed app is the better fit.
Using it on your phone
- Tap the location button to centre on where you are, or search an address.
- Drag the date and time sliders. They snap to the solstices, equinoxes, sunrise, solar noon and sunset.
- Read the sun's bearing and height in the panel. Pair the bearing with a compass to face the sun's position.
- Tap Share to send someone the exact view.
The link above opens Princes Street Gardens in Edinburgh on midsummer evening, when the sun sets well round in the north-west.
Limits. Buildings within 300 m load from OpenStreetMap, with a typical height assumed where none is mapped. Only individually mapped trees appear, in full leaf all year. Flat ground, clear skies.