Kaal Sarp Dosha

What this section adds to the calculator above

The calculator above gives a verdict, a direction, a margin and a short note on certainty. This section sits underneath it and covers what the short copy cannot: where the idea does and does not appear in the classical books this app is built from, the exact arithmetic the engine runs, how to read each field of every kind of result, several real runs of the engine set side by side, and the limits you should keep in mind. The shorter companion piece, Kaal Sarp Dosha is a question of geometry, makes the central argument in five minutes. This page is the reference behind it.

One framing note. Much popular writing on Kaal Sarp is written to frighten. This page does the opposite on purpose. The calculator measures seven angles against one line. Everything below is about how that measurement is made and how far it can be trusted, and nothing here predicts an event in anyone's life.

Where the idea appears in the sources, and where it does not

It is worth being exact about the pedigree, because the name sounds ancient. A search of the five astrology texts in this app's source library that have a searchable text layer - the Brihat Parashara Hora Shastra (BPHS), Kalyana Varma's Saravali, the Bhrigu Sutras, Daivajna Vallabha and Advanced Predictive Astrology - finds no spelling of Kaal Sarp in any of them. Not as a yoga, not as a dosha, not in passing. Two further books in the library are image-only scans that could not be searched, so the statement covers the searchable texts and no more.

What the search does turn up is three near-misses, and each is worth knowing because each is sometimes mistaken for a source.

Near-miss one: Sarpa Yoga

BPHS Ch. 35 lists 32 Nabhash Yogas: 3 Asraya, 2 Dala, 20 Akriti and 7 Sankhya. The two Dala yogas are Maal and Sarpa, and Sloka 8 defines them: benefics occupying the kendras produce Maal Yog, while malefics so placed cause Bhujang, or Sarpa Yog. Saravali gives the same pair in its Nabhasa chapter (Sloka 18): all angles occupied exclusively by benefics is Maala, malefics in all angles is Sarpa, and it adds that these two Dala yogas were explained by Parasara. That rule is about which grahas hold the angular houses. Rahu and Ketu play no part in it, and no axis is involved. This app computes it separately, inside the yogas calculator, where it looks at which of the seven grahas sit in houses 1, 4, 7 and 10 and reports Sarpa Yoga only when natural malefics hold at least three of those houses and no benefic holds any, as BPHS Sloka 8 words it.

The two texts are blunt about Sarpa Yoga. BPHS Ch. 35 Sl. 22 and Saravali Sl. 42 both describe hardship and a difficult disposition. This app's wording for that yoga is deliberately calmer, classically read as tending toward struggle and reversals rather than a fixed verdict. The point for this page is narrower: those lines describe the kendra rule. Quoting them as the classical description of Kaal Sarp attaches one rule's text to a different rule.

Near-miss two: three adjacent names in the Shashtiamsa list

BPHS Ch. 6 names the sixty divisions of the Shashtiamsa, and entries 15, 16 and 17 in that list are Kaal, Sarpa and Amrit. The words are side by side, which is striking, but they are the names of three consecutive half-degree slices of a sign, used by the Shashtiamsa (D60) calculator. Nothing in that chapter connects them to the lunar nodes or to the distribution of grahas around the chart.

Near-miss three: a numerology metaphor

The only place the phrase itself occurs in the text corpus is a numerology slide deck, Life With Number Magick Part 2, which calls one three-number line on its grid a Numerological Kaal Sarp Yog. That line is shown, with the book's own wording, in the Sepharial grid calculator. It is a borrowed label for a pattern of birth-date digits. It assumes the reader already knows the astrological term and defines nothing about it.

What the classical texts do establish

Two things the sources do say are directly relevant. First, BPHS Ch. 3 Sl. 10-11 names nine grahas and identifies Rahu and Ketu as the ascending and descending nodes of the Moon, counted among the malefics; Sloka 30 describes Rahu as smoky in appearance and says Ketu is akin to Rahu. So the texts treat the nodes as a pair with one nature, which is how an axis behaves. The longer treatments are in Rahu in Vedic astrology and Ketu in Vedic astrology.

Second, the classical yogas that describe how the whole chart is distributed count seven grahas, not nine. Saravali's Sankhya yogas begin with the words: if all the seven planets occupy one Rasi, Gola Yoga is formed, and continue through two signs, three, up to seven. BPHS Ch. 35 Sl. 16-17 gives the same ladder. The Kaal Sarp rule follows that convention: seven bodies are tested, and the nodes are left out because they are the line being tested against. That is a point of consistency with the classical way of counting, and no more than that. It does not make the rule classical.

The axis itself: what Rahu and Ketu are in this engine

Rahu here is the Moon's mean ascending node, the point where the Moon's orbit crosses the Sun's apparent path going north, averaged so that its short-term wobble is removed. The engine computes it from a polynomial in time, converts it to the sidereal zodiac with the Lahiri ayanamsa (the same offset shown by the ayanamsa calculator), and publishes it to four decimal places. Ketu is then set to Rahu plus exactly 180 degrees. It is never computed independently, so the two are opposite by construction and together they form a diameter of the chart.

The mean node moves backward through the zodiac. Running the engine's own formula a year apart gives a movement of 19.34 degrees a year against the direction the planets travel, which is one full circuit in about 18.6 years. That works out to a little over three arcminutes a day, and it agrees with the translator's note in BPHS Ch. 3, which lists the average daily motion of Rahu and Ketu as 3 arcminutes beside the Moon's 13 to 15 degrees and Saturn's 2 arcminutes.

Those speeds explain most of what the calculator returns. The axis turns slowly. Saturn and Jupiter drift slowly too, so whether the two of them are on the same side of the line is settled for months or years at a time. The Sun, Mercury and Venus sweep around once a year. The Moon crosses the whole zodiac in a month, so it spends roughly a fortnight on each side. The combination can only be present while the slow grahas already agree, the yearly ones have gathered on that side, and the Moon is passing through the same half. The general accuracy of these positions is set out on the methodology page.

Exactly how the verdict is computed

The function is computeKaalSarp in the kundali engine. It takes a chart that has already been cast and does the following, in this order.

1. 1.Take the sidereal longitude of each of the seven classical grahas: Sun, Moon, Mars, Mercury, Jupiter, Venus, Saturn.
2. 2.For each one, subtract Rahu's longitude and wrap the answer into the range 0 to 360. The result is how many degrees that graha sits ahead of Rahu, measured in the direction of the signs. This is the offset.
3. 3.If every offset is strictly greater than 0 and strictly less than 180, all seven are on the arc that runs forward from Rahu to Ketu. The verdict is present and the direction is recorded as Rahu to Ketu.
4. 4.If every offset is strictly greater than 180 and strictly less than 360, all seven are on the other arc. The verdict is present and the direction is Ketu to Rahu.
5. 5.In every other case - at least one graha on each side, or a graha sitting at exactly 0 or 180 - the verdict is not present and the direction is empty.
6. 6.For each graha, work out its distance to the nearer end of the axis: the smaller of its distance to Rahu and its distance to Ketu. The smallest of the seven is the margin, and the graha and node it belongs to are recorded with it.
7. 7.Subtract the smallest offset from the largest. That is the span, the width of the arc the seven grahas actually occupy.
8. 8.Shift Rahu by the difference between the true and mean node for that moment, run steps 2 to 5 again, and record whether the verdict changed. This is a probe only. The chart's Rahu is not moved.

There is no orb, no tolerance, no weighting and no table lookup anywhere in that list. The only constants are 0, 180 and 360. A reader with the seven longitudes and Rahu's longitude can repeat the whole verdict with seven subtractions, which is the reason the calculator prints every offset.

Two details of the output follow from the engine's own reasoning. The margin, nearest graha, nearest edge and span are returned only when the verdict is present. On a chart without the combination they would read as how close you came to having it, which is not something the rule recognises, so they are left empty. And the grahas are listed in order of offset, starting from Rahu and going round, so the table reads as a walk around the chart from the axis.

Reading each part of the result

The margin deserves a careful reading. It is not a strength. Nothing in the engine, and nothing in the library, says that a wide margin makes the combination stronger or a narrow one weaker. It is a statement about the measurement: how far the positions would have to be wrong, or how far the birth time would have to move, before the answer changed. The span is similar. A span of 60 degrees means the seven grahas are bunched in two or three signs; a span of 179 means they are spread across the entire half. Both are simply present under the rule.

Four real runs, side by side

Every number in this section came from running the engine on 6 October 2026. Nothing has been rounded beyond what the engine itself prints.

Run 1: present, with almost no margin

Birth at 12:00 IST on 12 January 1997, Delhi. Rahu is at 158.6469 degrees (Virgo), Ketu at 338.6469.

The seven grahas fill the half almost end to end: Mars is under six arcminutes inside one end and Saturn is 0.577 degrees inside the other. Here is the part a bare yes would hide. The project's check against a full ephemeris puts the engine's Mars within about one arcminute, so Mars's margin of under six arcminutes is only a few times the error of the position itself, and smaller than the difference between common ayanamsa values. So this verdict depends on a difference small enough that another program could place Mars on either side. The certainty note for this chart says as much by a different route: the true node sits 1.26 degrees back from the mean node at that moment, and measured from it Saturn's offset becomes 180.6853, over the line. The calculator keeps its mean-node verdict and calls the chart a genuine borderline case.

Run 2: present, comfortably

Birth at 12:00 IST on 31 August 2008. Rahu is at 293.4840 degrees (Capricorn). The offsets, in order, are Sun 200.7719, Saturn 203.8544, Moon 206.2834, Venus 223.3586, Mercury 225.4651, Mars 230.1430 and Jupiter 325.2538. All seven lie between 180 and 360, so the verdict is present on the arc from Ketu to Rahu. The nearest graha is the Sun, 20.7719 degrees from Ketu, and the span is 124.4819 degrees. The true node is 1.20 degrees from the mean node at that moment and the verdict is the same on both.

This is what a robust result looks like. A margin above 20 degrees is far beyond anything the node model, the engine's accuracy or a few hours of birth-time error could erase. Six of the seven grahas are within 30 degrees of each other in Leo and Virgo, with Jupiter alone further round in Sagittarius. If your own result looks like this one, the verdict is not in doubt as a matter of arithmetic. What it means is a separate question, taken up below.

Run 3: not present, clearly

Birth at 14:30 IST on 15 August 1985, Delhi. Rahu is at 19.5120 degrees. Venus (61.8322), the Moon (85.8745), Mars (90.4857), Mercury (91.8225) and the Sun (99.3122) are on the Rahu-to-Ketu arc. Saturn (188.6311) and Jupiter (267.5124) are on the other. Two grahas on the far side means the combination is not present, and the two that break it are the slowest ones, so no reasonable change to the birth time would alter the answer. Rahu is in house 6 and Ketu in house 12. No margin and no span are returned.

Run 4: not present, with one graha out

The sample person used across this app's worked examples was born at 06:42 IST on 14 August 1994 in Ahmedabad. Rahu is at 205.3976 degrees. Six grahas sit on the Ketu-to-Rahu arc: Mars 219.0194, Sun 271.8667, Mercury 272.9550, Venus 317.5192, Jupiter 348.1554 and the Moon at 359.2425, which is 0.7575 degrees short of Rahu. Saturn alone, at an offset of 111.1026, is on the other side. The verdict is not present, the same answer that the Mangal Dosha calculator shows for this person in its dosha list. Popular practice sometimes calls a chart like this a partial Kaal Sarp. The engine has no such category: one graha on the other side is absent, exactly as two would be.

The two certainty checks

Mean node or true node

There are two ways to place Rahu. The mean node is the smoothed position used throughout this app. The true node adds the short-term swings of the Moon's orbit back in; the engine approximates it by adding five periodic terms from Meeus's Astronomical Algorithms (Ch. 47) to the mean node. Across 1970 to 2015 the two differ by at most about 1.88 degrees. No text in the library says which one any rule was written for, so the app does not claim the question is settled. It keeps the mean node for the verdict, so that every page of the app reads the same Rahu, and reports what the other choice would have given.

In practice the note reads one of two ways. Either the verdict is the same on both nodes, as in Runs 2, 3 and 4, or it would differ, as in Run 1, and the chart is described as borderline. In the daily scan behind this calculator, 32 of 1,216 positive days changed verdict on the true node, about one in forty. A chart with a margin wider than 2 degrees cannot be among them, since the nodes never differ by that much in those years.

A graha exactly on the axis

Because longitudes are published to four decimal places, an offset of exactly 0 or exactly 180 does occur. The test uses strict inequalities, so a graha on the line counts as not between the nodes. At 05:54 IST on 17 July 1979, Saturn and Rahu are both at 137.2263 degrees, an offset of 0. The other six grahas have offsets from 230.1498 (the Moon) to 333.6311 (Mercury), all on the Ketu-to-Rahu arc. The verdict is not present, the graha table marks Saturn as on the axis, and the certainty note states that this policy decided the answer, that some practitioners would count Saturn as inside, and that the chart should be treated as borderline.

The engine's own comment is candid that this is a decision and not a finding. No source says which way an on-axis graha should count. The strict reading was kept because it is the one the kundali's dosha list had always used, and changing it would have altered existing users' charts without a sourced reason. The on-axis sentence appears only when the choice mattered, that is, when the remaining six grahas were all on one side.

Birth-time sensitivity

The verdict needs no birth place, but it does need a time, and the calculator refuses a date on its own. The reason is the Moon. Take 2 March 2000. At 00:00 IST the Moon's offset is 168.7627, on the Rahu-to-Ketu side, while the other six grahas are between 193.6872 and 280.4837 on the far side: not present. At 23:59 IST the Moon's offset is 180.8353. It has crossed Ketu, all seven are now on the Ketu-to-Rahu arc, and the verdict is present with a margin of 0.8353 degrees and a span of 99.7855. Interpolating between the two runs puts the change roughly an hour and forty minutes before midnight. Two people born on that date a few hours apart get opposite answers, and both are computed correctly. The Moon's own position at your birth is shown by the Moon sign calculator.

The Moon is the usual cause but not the only one. On 12 January 1997, the date of Run 1, Mars has an offset of 359.9399 at 00:00 IST, a hair short of Rahu, and the verdict is not present. By noon it is 0.0938 and by 23:59 it is 0.2454, present both times. A slow graha crossing the axis flips the verdict just as surely as the Moon does. It merely happens far less often.

Across the scanned years the verdict at 00:00 IST differed from the verdict at 23:59 IST on 204 of 16,436 days, 1.24 percent. That is a small share of all days but a large share of the positive ones, which is why the calculator will not default to noon. If your birth time is a window, run the calculator at both ends of it. If the two verdicts agree, the uncertainty in your time does not matter for this question. If they differ, the honest answer is that it depends on the minute, and what an unknown birth time costs explains what else in a chart shares that dependency.

Time zone matters for the same reason. When a birth place resolves, the app uses that place's time zone. When no place is given, the time is read as India Standard Time and the result is flagged as having an assumed zone. A birth abroad entered without a place is therefore shifted by the difference between that zone and IST, which can be many hours. Entering the place fixes this and also adds the houses, since the rising sign found by the Lagna calculator needs coordinates.

How often it is present, and why it clusters

Sampling the engine at noon IST on every day from 1 January 1970 to 31 December 2014 gives 1,216 positive days out of 16,436, about 7.4 percent. They are not spread evenly. Positives occurred in only 23 of those 45 calendar years, and they arrived in 102 separate unbroken runs, the longest lasting 15 days.

The pattern follows from the speeds described earlier. For seven years from 1988 to 1994 there is not a single positive noon, which is what you would expect while slower grahas sit on opposite sides of the axis, since nothing the faster ones do can then bring all seven together. When the slow ones do agree, positives come in bursts of up to about a fortnight, the time the Moon takes to cross one half of the zodiac, and a burst typically ends when the Moon steps over a node. The 15-day ceiling on a run is the Moon's doing.

Two consequences are worth stating plainly. First, people born in the same fortnight of a cluster year largely share the verdict, so it cannot by itself distinguish one of them from another. Second, of the 1,216 positive days, 517 had the grahas on the Rahu-to-Ketu arc and 699 on the Ketu-to-Rahu arc. Any scheme that gives the two directions different names is renaming hundreds of those days, and nothing in the library says which direction would carry which name.

What the calculator deliberately leaves out

• The twelve named types. Popular practice names a type according to the houses Rahu and Ketu occupy. The type field here is always empty and carries a sentence explaining that no searchable text in the library names Kaal Sarp at all, let alone twelve varieties of it.
• Kaal Amrit. One direction is popularly given this second name. The calculator reports the direction as a fact and attaches neither label.
• Partial or near-miss verdicts. One graha outside the arc is not present, as Run 4 shows. The margin is not reported for absent charts for the same reason.
• A tolerance orb. No source supplies one, so inventing a number of degrees within which a graha still counts would be a fabricated constant.
• Severity. The kundali's dosha list marks Kaal Sarp simply as present or absent. It carries no mild, moderate or strong grading, unlike Mangal Dosha in the same list.
• Remedies. The calculator promises no outcome, so there is nothing for a ritual, gemstone or donation to avert, and this app prescribes none anywhere.
• A prediction. The result is a description of where seven grahas stood relative to one line at one moment.

There is one place where the app does attach a line of interpretation. In the dosha list of the full kundali, a present Kaal Sarp carries a single sentence saying it is read as intensified, karmic-feeling timing rather than misfortune, and that effects vary by which houses Rahu and Ketu occupy. That sentence is the app's own cautious summary of common practice, not a quotation from a text, and it is why the house positions are the useful next step. For what the sources actually say about the nodes in a given house, see the house pages, for example Rahu in the 7th house and Ketu in the 1st house, the placement in Run 1.

How it connects to the rest of the app

The verdict on this page is not a private calculation. The dosha list on your full kundali and in the Mangal Dosha calculator calls the same function and reads its present-or-not answer, so the three can never disagree for the same birth details. Those two need a resolved birth place, because the rest of their dosha checks use houses. This page does not, which makes it the only route to a Kaal Sarp verdict for a reader whose town will not resolve. The background to the dosha list is in Mangal Dosha: what it is and is not.

For the chart-wide patterns that the classical texts do define, use the yogas calculator: it tests the Sankhya, Asraya and Dala yogas of BPHS Ch. 35 and Saravali, including Sarpa Yoga, and what a yoga in your chart means explains how to weigh them. BPHS Ch. 35 Sl. 50 says the results of the Nabhash yogas are felt throughout all dasha periods; the library makes no such statement about Kaal Sarp, because it makes no statement about Kaal Sarp at all.

For timing, the periods ruled by the nodes are covered in Rahu Mahadasha and Ketu Mahadasha, and the Vimshottari Dasha calculator shows when they fall for you. Where the nodes are today relative to your Moon is part of the Gochar calculator. And to see the whole chart the seven offsets were taken from, cast it with the birth chart tool. The related question of why two apps can place the same body differently is taken up in why apps disagree on your nakshatra.

Frequently asked questions

Is Kaal Sarp Dosha mentioned in Brihat Parashara Hora Shastra?

Not in the translation this app is built from. A search of that text finds no spelling of Kaal Sarp. It defines Sarpa Yoga in Ch. 35 Sl. 8, which is malefics occupying the kendras, a different rule with no reference to Rahu or Ketu. Saravali, the Bhrigu Sutras, Daivajna Vallabha and Advanced Predictive Astrology were searched with the same result.

Another site says I have Kaal Sarp and this calculator says I do not. Why?

There are four usual causes, and the result shows you which applies. The other site may use the true node, in which case the certainty note here will say the verdict differs on it. It may count a graha on the axis, or one just outside the arc, as included; this engine uses a strict test with no orb. It may be using a different birth time or time zone. Or its planetary positions may differ by a few arcminutes, which matters only when your margin is that small. Compare the offsets in the table with the other site's longitudes, and see the methodology page for how positions are computed here.

Which type of Kaal Sarp do I have?

The calculator does not name one. The twelve popular type names are assigned from the houses Rahu and Ketu occupy, and when your birth place resolves the result shows those houses, so nothing needed for the popular scheme is hidden. What is withheld is the label and any meaning attached to it, because no searchable text in the library contains either.

Does a smaller margin mean a weaker dosha?

No. The margin describes how close the verdict came to being different, not how strongly anything applies. A margin of 0.09 degrees and a margin of 20 degrees are both simply present under the rule. The small one tells you the answer is sensitive to the node model, to the engine's accuracy and to your birth time. The large one tells you it is not.

One of my planets is just outside the arc. Is that a partial Kaal Sarp?

The engine has no partial category. If any one of the seven grahas is on the other side of the axis, the verdict is not present, and no margin is reported. The graha table still shows every offset, so you can see which graha is outside and by how much, but the app does not turn that into a diluted version of the combination.

Why does the calculator insist on a birth time?

Because the verdict can change within a single day. On 2 March 2000 it is not present at 00:00 IST and present at 23:59 IST, since the Moon crosses Ketu that evening. Across 1970 to 2014 the two ends of the civil day gave different verdicts on 204 of 16,436 days. Assuming noon would hide that, so a date without a time is refused instead.

Do I need to enter a birth place?

Not for the verdict, which uses longitudes only. A place does two things: it supplies the correct time zone, where otherwise India Standard Time is assumed, and it lets the result show which houses Rahu and Ketu occupy. Without a resolved place the house fields are left empty and the result says so.

Why are Rahu and Ketu not counted among the planets being tested?

They define the line. Ketu is set to Rahu plus 180 degrees, so the two are the ends of the axis and cannot be on either side of it. Testing seven grahas also matches how the classical distribution yogas are counted: Saravali's Sankhya yogas speak of all the seven planets.

Does the result predict difficulty in my life?

The calculator makes no prediction. It reports a geometric fact about your birth moment, shared with most people born in the same fortnight. The one interpretive sentence the app attaches, in the kundali's dosha list, describes it as read as intensified timing and not misfortune, and points to the houses of Rahu and Ketu as the thing that varies between charts.

Does Kaal Sarp come and go in the sky today?

The same geometry can be tested for any moment, and in the scanned years it came in runs of up to 15 days, separated by gaps as long as seven years. This calculator applies the test to a birth moment only. It does not report whether the pattern holds in today's sky.