Free Qi Men Dun Jia Calculator: Automatic Time Zone, DST and True Solar Time
What the calculator corrects automatically
| Correction | How it works |
|---|---|
| Time zone | Read from your device clock, so New York, London, Sydney or Beijing all start from the right local time. |
| Daylight saving time | Your device knows whether DST is in effect for the date; the calculator removes it so the chart uses standard time. |
| Longitude | Each degree away from your time zone's reference meridian shifts the sun by 4 minutes. Use the GPS button, a city preset or type your longitude (west is negative). |
| Equation of time | The seasonal difference between clock noon and solar noon, from about −14 to +16 minutes, is added for the exact date. |
| Solar terms | Calculated from the sun's actual ecliptic longitude, not a lookup table, so the chart switches at the true moment of each term. |
These corrections apply to charts cast for now or for a date and time you choose. For a birth chart, convert the birth time to True Solar Time by hand first; here is how to do it for births abroad.
How to cast a chart
- Open the calculator and tap the GPS button, or choose your city. If you skip this, the calculator assumes the center of your time zone.
- Choose Now, or pick a date, time and time zone to cast for another moment.
- Pick what you are asking about (career, wealth, relationships, health or general).
- Cast the chart. You get the full nine palaces: stems, eight doors, nine stars and eight deities, with the Chief Star and Chief Door marked.
- Sign in (free) to open each palace's detailed reading, the day's scores and the AI interpretation of your question.
What is free
- Casting and viewing the full nine-palace chart: always free.
- A free account includes a 30-day full trial with 5 AI readings a day, no card required.
- After the trial, Pro ($15.99/month) unlocks unlimited AI readings, daily scores, golden hours and chart history.
Which method does it use?
Hour-based Qi Men (时家奇门), with the Chai Bu (拆补) method to set the ju and the rotating plate (转盘) to lay out stars, doors and deities. The same time and place always produce the same chart. Read why we chose these methods.
Want to check our math? The rules, a worked example and a comparison with Hong Kong Observatory solar-term data are public. See the rules and verification.
FAQ
Do I need to convert my time to Beijing time?
No. Qi Men uses the True Solar Time where you are. The calculator starts from your device's local clock and converts it for you; converting to Beijing time by hand would make the chart wrong.
Does it handle daylight saving time in the US, Canada, Europe and Australia?
Yes, both for the present moment and for a date and time you choose. The time zone's rules say whether DST applies on that date, and the calculator removes it before correcting for longitude and the equation of time.
Is the Qi Men Dun Jia calculator really free?
Yes. Casting and viewing the full chart is free. A free account adds a 30-day trial with AI readings; ongoing AI readings require Pro at $15.99 a month.