House Facing from a Map
Flying stars start from a single number — the direction the front of the house faces. You can take it from a map: mark the house, drag an arrow toward the street, and the calculator will convert the azimuth into a compass reading, allowing for magnetic declination, and build the chart of the house.
The map loads from OpenStreetMap servers only after you press “Open map,” and the address goes to OpenStreetMap search only when you press “Search.” The house coordinates stay in your browser and never go into the page address.
How to Use It
- Press “Open map” and find your house — by searching for the address or by hand.
- Click on the house: the circle of 24 mountains and an arrow will appear.
- Drag the gold arrow in the direction the house faces — usually toward the street or the main entrance. The circle is rotated by the magnetic declination, so its divisions match what a luopan compass would show at the house.
- Below the map you will see the facing azimuth by map and by compass, and the full flying star chart for the selected construction period.
If you know the front is turned slightly differently from the wall on the map, enter an adjustment in degrees: plus means clockwise.
Why the declination correction is needed
A map shows geographic north, while a compass needle points to magnetic north. The angle between them, the magnetic declination, depends on the place and slowly changes over time: currently about +12° in Moscow, about +2° in Novosibirsk, about +1° in London, and about −10° in Kamchatka.
In the classical schools, flying stars are read from a luopan, that is, by magnetic north. So the calculator subtracts the declination from the map azimuth. The declination is calculated with the World Magnetic Model WMM2025 — the same one built into navigation devices and smartphones; the model is valid until the end of 2029.
Where the map can be wrong
- Building outlines on OpenStreetMap are drawn by volunteers, and for older buildings they can be off by a couple of degrees.
- Local magnetic anomalies and metal in the house are invisible to the model. If a compass at the entrance shows something different, trust the compass, but keep it away from cars and steel reinforcement.
- The facing is not always where the street is. Schools disagree on whether the facing is the side with the entrance, the brightest side or the side toward the road. The calculator uses the direction you specify.
If the facing falls on the boundary between two mountains — within one and a half degrees — the result will include a warning: traditionally such a house needs a separate analysis.
What next
How to read the mountain and water stars, formations and annual stars is explained on the flying stars page. There you can also recalculate the chart for another year and month by entering the facing degrees.
Related in This Section
Frequently asked questions
Do I need a compass?
No: the azimuth is taken from the map, and the declination is calculated from a model. But if you have a compass, check the result at the entrance — that is the best test.
Where do my coordinates go?
Nowhere except your browser and the link to the calculation. Your browser loads the map images from OpenStreetMap servers, which can see the part of the map you are viewing. Address search sends the text you type to the OpenStreetMap Nominatim service — only when you press “Search.”
How is this different from simply entering degrees?
The calculation is the same — it is the same flying star calculator. The map just saves you the compass and shows how the 24 mountains lie over your house.