Two apps can date the same person's sade sati 143 days apart. Sade sati runs while Saturn passes through three signs in a row. The middle one is your Moon sign, the sign the Moon was in when you were born. The other two are the signs on either side of it. The dates are the moments Saturn crosses into and out of that band of three signs. Saturn's stay in the 4th or 8th sign from the Moon has its own name, dhaiya.
Apps disagree because Saturn rarely crosses a sign line just once. For about four and a half months each year, it seems to move backward. Near a sign line, that loop can carry it out of the band and back in. An app that adds 7.5 years to the first date misses all of that.
Take John Doe, born Aug 15, 1990, at 10:30 AM in New York, with his Moon in Taurus. His next sade sati runs from June 2, 2027 to July 12, 2034, which is 2,597 days. The simple count of 7.5 years ends on December 2, 2034, 143 days too late. In the middle, Saturn also leaves the band for 127 days. The time zone and the ayanamsa, which sets where the Vedic zodiac starts, move the dates again.
The rule: three signs around the Moon sign
Saturn moves slowly. It takes about 29.5 years to go around all 12 signs, so it stays about 2.5 years in each one. Sade sati covers three of those signs, counted from the birth Moon (rule SS-01). Each sign is one phase:
Phase | Where Saturn is | For a Taurus Moon |
|---|---|---|
Rising | The sign before the Moon sign (12th from it) | Aries |
Peak | The Moon sign itself (1st) | Taurus |
Setting | The sign after the Moon sign (2nd) | Gemini |
In the tradition, sade sati is a slow, testing time. This post covers only its dates. The sade sati glossary entry has the short definition.
Everything starts from the Moon sign. The API finds it from the Moon's sidereal place, which is its place measured against the stars. A wrong Moon sign moves every date. For an Aries Moon, the band starts on March 29, 2025, which is 795 days before John's.
Why Saturn crosses the same line more than once
Each year, Saturn turns retrograde for a few months. Retrograde means it seems to move backward when seen from Earth, because the two planets circle the Sun at different speeds. In 2026, Saturn is retrograde from July 26 to December 10, New York time. In India, it turns direct (starts moving forward again) on December 11, 2026. Both dates come from GET /v1/sky/events, part of the transit API. Saturn's other sign changes are in our post on Jupiter, Saturn, Rahu and Ketu transits.
When that loop happens near a sign line, Saturn often crosses it three times. It moves forward into the next sign, slips back out, then crosses forward again. A correct calculation finds every one of those crossings (rule SS-03).
Our API checks Saturn's place every 5 days, for 100 years from birth. When the sign changes between two checks, it narrows down the exact moment. Crossings less than a year apart belong to one sade sati. Any time Saturn spends back outside the band becomes a break. A year is a safe cutoff. The longest break in the charts checked for this post lasts 189 days. John's last sade sati ended in May 2005, 22 years before his next one.
Worked example: John Doe's next sade sati
John Doe, born Aug 15, 1990, 10:30 AM, New York (America/New_York). Moon in Taurus. Request: POST /v1/sadesati?as_of=2026-10-23. All times are New York time. Run on October 11, 2026.
On October 23, 2026, the response says "present": false, so sade sati is not running for John. The next block holds the coming one as a list of Saturn's stays. Here it is as crossings:
Saturn enters | Sign | What starts |
|---|---|---|
Jun 2, 2027, 7:58 PM | Aries | Rising phase |
Oct 19, 2027, 9:42 PM | Pisces | Break (127 days) |
Feb 23, 2028, 8:54 AM | Aries | Rising again |
Aug 8, 2029, 3:02 AM | Taurus | Peak |
Oct 5, 2029, 7:22 AM | Aries | Back to rising |
Apr 16, 2030, 11:37 PM | Taurus | Peak again |
May 30, 2032, 5:30 PM | Gemini | Setting phase |
Jul 12, 2034, 6:52 PM | Cancer | Sade sati ends |
The break comes back in its own list, with a reason:
"breaks": [
{
"starts": "2027-10-19T21:42:17",
"ends": "2028-02-23T08:54:04",
"reason": "Saturn retrograde back out of the band"
}
]So one sade sati takes eight crossings. Saturn touches Taurus for 58 days, then slips back into Aries for 193 days before it settles.
Each phase runs from first entry to final exit
Grouped by phase, the stays give three spans, each from Saturn's first entry to its final exit:
Phase | First entry | Final exit | Saturn comes back |
|---|---|---|---|
Rising (Aries) | Jun 2, 2027 | Apr 16, 2030 | Feb 23, 2028 to Aug 8, 2029, and Oct 5, 2029 to Apr 16, 2030 |
Peak (Taurus) | Aug 8, 2029 | May 30, 2032 | Apr 16, 2030 to May 30, 2032 |
Setting (Gemini) | May 30, 2032 | Jul 12, 2034 | No |
The phases overlap. The peak first starts on August 8, 2029, but the rising phase lasts until April 16, 2030. Those two dates are 251 days apart.
An app that ends each phase when the next one first starts says John's rising phase ends on August 8, 2029. An app that waits for Saturn to settle starts his peak on April 16, 2030. Both read the same sky. They pick different crossings.
The simple 7.5-year count against the real span
The shortcut adds 7.5 years to the first entry, or 2.5 years to each phase. For John, it gives these dates:
Phase | Simple count | Computed | Difference |
|---|---|---|---|
Rising | Jun 2, 2027 to Dec 2, 2029 | Jun 2, 2027 to Apr 16, 2030 | Ends 135 days later |
Peak | Dec 2, 2029 to Jun 2, 2032 | Aug 8, 2029 to May 30, 2032 | Starts 116 days earlier |
Setting | Jun 2, 2032 to Dec 2, 2034 | May 30, 2032 to Jul 12, 2034 | Ends 143 days earlier |
Seven and a half years from John's first entry is 2,740 days. The computed span is 2,597 days. Take out the 127-day break, and Saturn spends 2,470 days in the band.
The length is not fixed either. It changes with the Moon sign. Here are the three Moon signs in sade sati on October 23, 2026, plus John's, in New York dates:
Moon sign | First entry | Final exit | Days |
|---|---|---|---|
Aquarius | Jan 23, 2020 | Feb 23, 2028 | 2,953 |
Pisces | Apr 28, 2022 | Apr 16, 2030 | 2,910 |
Aries | Mar 29, 2025 | May 30, 2032 | 2,619 |
Taurus (John) | Jun 2, 2027 | Jul 12, 2034 | 2,597 |
None of the four is 7.5 years long. The longest and the shortest differ by 356 days.
Check any birth date for free. The sade sati calculator draws each stay on a timeline, with gaps where Saturn steps back out.
Five settings that change the dates
The counting method. Real crossings or a flat 7.5 years. For John, this alone moves the end date by 143 days.
Breaks. Saturn is back in Pisces from October 19, 2027 until February 23, 2028. On those dates the API returns "present": false and "in_break": true, with current still set. An app that ignores breaks says John is in sade sati all winter. One that splits at the break shows two short sade satis.
Phase edges. First entry or final settling. John's peak starts on August 8, 2029 or April 16, 2030, depending on the choice.
The ayanamsa. The ayanamsa is the offset between the Western and the Vedic zodiac. The API offers three: Lahiri (the default), KP and Raman. With KP, John's sade sati starts on June 1, 2027, about one day before the Lahiri date. With Raman, it starts 14 days earlier, on May 19, 2027, and ends 11 days earlier, on July 1, 2034. Raman also puts Saturn in Gemini from September 21 to October 18, 2031. So John's setting phase first starts 252 days earlier.
The time zone. John's sade sati starts at 7:58 PM on June 2, 2027, in New York. In India, it is already 5:28 AM on June 3. Five of his eight crossings fall on a different date in India. The day Saturn turns direct moves too, from December 10 in New York to December 11 in India.
See the full response. Try POST /v1/sadesati with any birth details in the API reference. Accounts open on November 26, 2026.
What to show your users
Show each phase from first entry to final exit, with the returns listed under it. Show a break as its own row, with both dates.
Print dates in the user's time zone. The API gives them in the time zone you send with the birth details. If the user now lives elsewhere, convert them.
Name the ayanamsa on the screen. Every response has a meta block with its name and value. When a user reports a date, send the same as_of they saw, and you get the same answer.
Sade sati dates are Saturn's crossings, nothing more. Apps differ when one skips crossings, rounds to 7.5 years, or uses another ayanamsa or clock. Return every crossing and show your settings, and any user can check your dates against another app.
