A Flying Star calculator builds your home’s Xuan Kong (玄空飞星) chart from two inputs: the exact facing direction and the period the building belongs to. It shows three numbers in each of nine sectors, the base, mountain and water stars, plus the current year’s star. Reading those numbers tells you which rooms suit rest, work or activity.
What do you need before you start?
You need the facing direction in degrees and the building’s period. Both decide the whole chart, so take care with each.
| Input | How to find it | Common mistake |
|---|---|---|
| Facing direction | Stand at the main door or main balcony, facing out, and read a compass in degrees | Reading near metal railings or lift lobbies, which pulls the needle |
| Period | The 20-year period when the building was completed (TOP) or last fully renovated | Using the purchase year instead of the completion year |
| Year | The year you want to read, for the annual overlay | Forgetting the solar year changes at Li Chun (立春), around 4 February |
Period 8 ran from 2004 to 2023. Period 9 runs from 2024 to 2043, so a building completed in or after 2024 uses a Period 9 chart.
How do you read the chart?
Each sector shows three stars: the base (运) star, the mountain (山) star and the water (向) star. In iGeomancy’s Flying Star calculator, each palace lists all three, plus the annual star for the year you choose.
- Mountain star (山星): traditionally linked to people, health and relationships; read it for bedrooms and quiet rooms.
- Water star (向星): traditionally linked to wealth and activity; read it for living areas, entrances and work areas.
- Base star (运星): the period’s own star in that sector, the background for the other two.
- Annual star: the star visiting the sector this year, which can support or strain it for the year.
In Period 9, the timely star is 9, so sectors where the mountain or water star is 9 are the ones practitioners usually make most of.
A worked example: a home facing North (子向) in Period 9
Hypothetical illustration. The chart below is computed by the calculator’s engine for a home facing North 2 (子, 0°) built in Period 9.
For a 午山子向 home (sitting South, facing North) in Period 9, both the mountain star and the water star in the North sector are 9. This pattern is called 双星到向, “double stars at the facing”. In the South, the sitting side, the mountain star is 8 and the water star is 1.
Practitioners read this chart as favouring an active, open facing side, such as a main entrance, living area or work space in the North. The sitting side is read as weaker for rest and relationships in this period, so they look at it carefully when deciding where bedrooms go.
What does 2026 add?
In 2026, the annual star 1 sits in the centre, and the Five Yellow (五黄) sits in the South. Practitioners keep the sector holding the annual Five Yellow quiet that year: no renovation or heavy activity there. The 2026 year (丙午) also places the Grand Duke (太岁) in the South and the Year Breaker (岁破) in the North, so many practitioners avoid starting renovation in either sector this year.
When should you check with a practitioner?
Check with a practitioner when the reading would change where you sleep, work or renovate. A calculator is only as good as its inputs. Measuring a facing direction in a high-rise can be tricky, and the reading of a chart depends on the actual layout, the surroundings and the people living there.
Get your home’s chart read by iGeomancy
Start with the free Flying Star calculator and the Period 9 HDB analyser. For an on-site measurement and a written plan for your home, book an iGeomancy feng shui consultation.
Frequently Asked Questions
What is a Flying Star calculator?
A tool that computes a building’s Xuan Kong Flying Star chart from its facing direction and period, showing the base, mountain and water stars for each of nine sectors.
Which period is my HDB flat?
Use the completion (TOP) year: 2004 to 2023 is Period 8, and 2024 to 2043 is Period 9. Practitioners differ on whether a major renovation changes the period, so ask if your flat was fully renovated.
What does “double stars at the facing” mean?
Both the mountain and water star 9 (in Period 9) land in the facing sector. Practitioners read it as favouring an active facing side.
Why does the exact degree matter?
Each of the eight directions is split into three 15-degree mountains, and the chart can change between them. A few degrees can move a home into a different chart.
Is a calculator enough on its own?
It is a good start. An on-site check confirms the facing direction and reads the chart against the real layout.
iGeomancy calculators and articles are guidance for arranging your space. They are not a guarantee of outcomes or a substitute for professional advice.