Birth Date Compatibility Calculator: In Indian numerology, the day of the month you were born gives your Mulank, or root number, and each root number is ruled by a planet. Birth date compatibility compares two people’s root numbers through the traditional friendships and enmities between their planets, as a picture of everyday, day-to-day chemistry. The calculator below does it in a second, shows the working, and tells you which birth days share your root number, because only the day matters here: the month and year make no difference.
This is also one of the most disputed questions in popular numerology. Five sources we compared gave different verdicts for the same pairs, and some of them contradict themselves. So this page shows exactly what its score chart is based on, how closely it follows the classical planetary friendship table, where it departs from it, and how other sources read the same pairs. Treat the result as a light, traditional look at how two temperaments meet, never as a verdict on a relationship.
Birth Date Compatibility Calculator Online
Birth Date Compatibility Calculator
Choose the day of the month each person was born to see your root-number (Mulank) compatibility. Only the day matters here; the month and year make no difference.
Please select both birth days.
What Is Birth Date Compatibility?
Your Mulank, also called the psychic number or driver number, is your birth day reduced to a single digit. It is read as your instinctive, everyday nature: how you react, what you need from the people you live with, and the rhythm you bring to a shared day. Each root number has a ruling planet: 1 the Sun, 2 the Moon, 3 Jupiter, 4 Rahu, 5 Mercury, 6 Venus, 7 Ketu, 8 Saturn and 9 Mars. Birth date compatibility asks how those two planets get along.
The idea of planetary friendship comes from Vedic astrology. In the classical scheme, each planet counts some planets as friends, some as neutral and some as enemies, and the relationship is not always mutual: one planet can treat another as a friend while the other treats it as an enemy. The same table is used in kundli matching, in the part of Ashtakoot matching called Graha Maitri, where the lords of the two partners’ Moon signs are compared and scored out of 5 of the 36 gunas. This calculator borrows that idea but applies it to birth-day numbers instead of Moon signs. It is a numerology reading, not a kundli match, and it does not replace one.
Because only the day matters, everyone born on the 5th, 14th or 23rd of any month shares root 5 and gets exactly the same result with a given partner. About one couple in nine shares the same root number.
How Is Birth Date Compatibility Calculated?
Each person’s birth day is reduced to one digit, and the two root numbers are looked up in this page’s score chart. Here is a worked example you can try: one person born on the 14th, the other on the 6th.
- Person 1. 14 gives 1 + 4 = 5, ruled by Mercury. Root 5 covers everyone born on the 5th, 14th or 23rd.
- Person 2. 6 is already a single digit, ruled by Venus. Root 6 covers everyone born on the 6th, 15th or 24th.
- The planets. In the classical table, Mercury counts Venus as a friend and Venus counts Mercury as a friend, so they are mutual friends, the strongest relationship in Graha Maitri.
- Score. The chart gives 5 and 6 a score of 86, which falls in the Excellent band.
The bands are fixed: 85 or more is Excellent, 75 to 84 Very Good, 65 to 74 Good, and 55 to 64 Moderate. The chart’s scores run from 55 to 88, so no pair ever lands below Moderate, and the calculator’s lowest band, Challenging, never actually appears. The chart is symmetric, so it does not matter who is Person 1. And the percentage sign is a convention: 86 means “near the top of this page’s own scale”, not an 86% chance of anything.
Why Another Calculator May Give You a Different Match
Mulank compatibility lists disagree more than almost anything else in popular numerology. Here are eight pairs as read by this page and by four other sources: the classical planetary friendship table, scored as Graha Maitri points out of 5; the favourable-number rule used on our own Love Compatibility page; the friend and enemy table repeated across many Hindi news sites; and one English Vedic numerology calculator.
| Pair | This page | Classical Graha Maitri | Our Love Compatibility rule | Hindi news table | An English Vedic calculator |
|---|---|---|---|---|---|
| 1 and 2 (Sun, Moon) | 88, Excellent | 5 of 5, mutual friends | Favourable | Friends | Poor |
| 1 and 5 (Sun, Mercury) | 78, Very Good | 4 of 5 | Favourable | Enemies | Good |
| 1 and 6 (Sun, Venus) | 58, Moderate | 0 of 5, mutual enemies | Not favourable | Friends | OK |
| 2 and 5 (Moon, Mercury) | 88, Excellent | 1 of 5, friend one way, enemy the other | Favourable | Enemies | OK |
| 6 and 8 (Venus, Saturn) | 86, Excellent | 5 of 5, mutual friends | Favourable | Friend one way, neutral the other | Poor |
| 1 and 4 (Sun, Rahu) | 55, Moderate | No classical entry for Rahu | Favourable | Enemies | OK |
| 2 and 4 (Moon, Rahu) | 55, Moderate | No classical entry for Rahu | Not favourable | Friends | Poor |
| 4 and 9 (Rahu, Mars) | 55, Moderate | No classical entry for Rahu | Not favourable | Friends | Poor |
No row gets the same verdict from all five sources. Sun and Moon are mutual friends in the classical table and friends in the Hindi table, yet the English calculator rates them Poor. Sun and Venus are mutual enemies classically, yet the Hindi table calls them friends. Venus and Saturn are one of the firmest friendships in the classical scheme, and the English calculator still rates them Poor. Here is where the differences come from.
- Which friendship table. The classical table, given in the Brihat Parashara Hora Shastra and repeated in later texts, covers only the seven visible planets. Many numerology sites use tables of their own that do not follow it, and the Hindi table widely repeated in news articles differs from it on several pairs.
- What to do with Rahu and Ketu. Roots 4 and 7 are ruled by Rahu and Ketu, which have no entry in the classical table, so every source improvises. One common version makes Rahu a friend of Mercury, Venus and Saturn and an enemy of the Sun, the Moon and Mars; another makes Ketu a friend of the Sun, the Moon and Mars; a third makes both nodes friends of Saturn and Venus. This is why the pairs involving 4 and 7 disagree most.
- Which numbers are compared. This page uses only the Mulank. Many practitioners also compare the two Bhagyanks, from the full birth dates, and our Love Compatibility page uses the Life Path number. Different numbers, different answers.
- How the score is built. Some calculators blend several factors, some use a simple good, neutral and poor grid, and some, like this one, use a fixed table of scores. A number from one site cannot be compared with a number from another.
- Plain inconsistency. The English calculator we checked lists 5 and 9 as a compatible pair in its FAQ, but its own summary table leaves each out of the other’s compatible list. A Hindi newspaper article on Mulank 1 recommends partners with roots 2, 3, 7 and 9 because their planets are friends of the Sun, although Ketu, the ruler of 7, has no place in the classical friendship table, and the article goes on to discuss only 2, 3 and 9.
The practical lesson is the same as on every compatibility page: choose one method, understand what it is based on, and do not collect the best verdict from several sites.
How Each Root Number Gets Along Day to Day
For each root number: how it tends to behave in shared daily life, where that goes wrong, its best and lowest partners on this page’s chart, and how the classical table sees its planet.
Root 1: The Sun
A root 1 brings direction to daily life: it plans the weekend, makes the call and decides where the family is going. Partners often appreciate not having to decide everything themselves. Where it goes wrong is deciding for two without asking, and impatience with anyone who wants more time to think. On this page, root 1 scores highest with roots 2, 3 and 9 (all 88), which matches the classical table, where the Sun’s friends are the Moon, Jupiter and Mars. It scores lowest with 4 and 8 (both 55) and 6 (58); the Sun counts Saturn and Venus as enemies. The Hindi news table disagrees sharply for 1, listing 6 as a friend and 5 as an enemy.
Root 2: The Moon
A root 2 is attentive, gentle and tuned to the mood of the house, the person who notices before anyone else that something is wrong. Where it goes wrong is quiet hurt: a 2 may withdraw rather than say what upset them, then feel unheard when nobody guessed. On this page, root 2 scores highest with 1 (88) and 5 (88), and lowest with 4 and 8 (both 55). The pairing with 5 is this chart’s most doubtful score. In the classical table, the Moon counts Mercury as a friend but Mercury counts the Moon as an enemy, which is worth only 1 point of 5 in Graha Maitri, and the Hindi news table calls 2 and 5 enemies outright. Read that result with extra caution.
Root 3: Jupiter
A root 3 is cheerful, sociable and generous with advice, the person who fills the house with guests and opinions. Where it goes wrong is lecturing, over-committing the household to plans, and treating a partner’s problem as something to fix rather than listen to. On this page, root 3 scores highest with 1 and 9 (both 88), matching Jupiter’s classical friends, the Sun and Mars. It scores lowest with 4 (55) and in the Moderate band with 5 (60) and 6 (62), reflecting the classical view that Jupiter counts Mercury and Venus as enemies. The Hindi table adds a twist of its own: it lists 3 as an enemy of itself.
Root 4: Rahu
A root 4 is practical and dependable, with an unconventional streak: the partner who has a system for everything, until they suddenly change it. Where it goes wrong is stubbornness and a habit of springing decisions on others. On this page, root 4 scores highest with 5 and 8 (both 86) and 6 (84), and lowest with 1, 2, 3 and 9 (all 55), following the common view of Rahu as a friend of Mercury, Venus and Saturn. Here our own site disagrees with itself: the favourable-number rule on our Love Compatibility page counts 1 as favourable for 4, and does not count 5 or 6. Because Rahu has no classical entry, no source can settle it.
Root 5: Mercury
A root 5 is chatty, flexible and restless, the one who suggests the outing, the change of plan and the new restaurant. Where it goes wrong is scattered attention: forgotten chores, plans changed without warning, and boredom with routine that the other person reads as boredom with them. On this page, root 5 scores highest with 2 (88) and with 4 and 6 (both 86), and lowest with 3 (60) and 9 (62), since Jupiter and Mars both count Mercury as an enemy in the classical table. The Hindi table is far harsher, listing 1, 2 and 5 itself as enemies of 5.
Root 6: Venus
A root 6 is warm, home-loving and sociable, the person who makes a house feel lived in and remembers everyone’s favourite food. Where it goes wrong is people-pleasing: saying yes to every family demand, then quietly resenting it. On this page, root 6 scores highest with 5 and 8 (both 86), Venus’s classical friends Mercury and Saturn, and lowest with 1 (58) and 3 (62), since Venus counts the Sun as an enemy and Jupiter counts Venus as one. The Hindi table reverses much of this, calling 1 a friend of 6 and 2, 3, 4 and 9 its best friends.
Root 7: Ketu
A root 7 is private and reflective, happiest with quiet time and a few close people. Where it goes wrong is withdrawal: long silences that the other person takes personally, and a detachment from daily practicalities that leaves the partner carrying them. On this page, root 7 is the steadiest number of all: every pairing scores between 68 and 78, so it has no Excellent partner and no Moderate one. That flat row is effectively a neutral compromise, because Ketu has no classical entry and the tables that exist contradict each other, some making it a friend of the Sun, the Moon and Mars, others an ally of Saturn and Venus.
Root 8: Saturn
A root 8 is serious, dutiful and slow to warm up, the partner who keeps the accounts and the promises. Where it goes wrong is rigidity, putting work first, and a pessimism that can dampen a lighter partner’s plans. On this page, root 8 scores highest with 4 and 6 (both 86), matching Saturn’s classical friends Venus and, in the common Rahu table, Rahu. It scores lowest with 1, 2 and 9 (all 55), because Saturn counts the Sun, the Moon and Mars as enemies. The Hindi table treats 8 as neutral with almost everyone and lists 3 as its only enemy.
Root 9: Mars
A root 9 is energetic, protective and quick to act, the partner who fixes the leaking tap at midnight and defends you in any argument. Where it goes wrong is temper, impatience and arguments that flare over small things. On this page, root 9 scores highest with 1 and 3 (both 88), Mars’s classical friends the Sun and Jupiter, and lowest with 4 and 8 (both 55), with 5 in the Moderate band at 62, because Mars counts Mercury as an enemy. The Hindi table lists no enemies at all for 9.
The Full Score Chart Used by This Calculator
Find the first root number down the left and the second along the top. The chart is symmetric, so the order does not matter. Scores of 85 or more are Excellent, 75 to 84 Very Good, 65 to 74 Good, and 55 to 64 Moderate.
| Root | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |
|---|---|---|---|---|---|---|---|---|---|
| 1 (Sun) | 82 | 88 | 88 | 55 | 78 | 58 | 68 | 55 | 88 |
| 2 (Moon) | 88 | 82 | 76 | 55 | 88 | 66 | 68 | 55 | 76 |
| 3 (Jupiter) | 88 | 76 | 82 | 55 | 60 | 62 | 70 | 68 | 88 |
| 4 (Rahu) | 55 | 55 | 55 | 78 | 86 | 84 | 74 | 86 | 55 |
| 5 (Mercury) | 78 | 88 | 60 | 86 | 84 | 86 | 76 | 80 | 62 |
| 6 (Venus) | 58 | 66 | 62 | 84 | 86 | 84 | 74 | 86 | 66 |
| 7 (Ketu) | 68 | 68 | 70 | 74 | 76 | 74 | 78 | 74 | 68 |
| 8 (Saturn) | 55 | 55 | 68 | 86 | 80 | 86 | 74 | 82 | 55 |
| 9 (Mars) | 88 | 76 | 88 | 55 | 62 | 66 | 68 | 55 | 84 |
What Our Own Calculation Shows
How closely the chart follows the classical table
We scored every pair of the seven classical planets by the Graha Maitri rule used in kundli matching, where mutual friends get 5 points, a friend and a neutral 4, two neutrals 3, a friend and an enemy 1, a neutral and an enemy half a point, and mutual enemies 0, and compared the result with this page’s chart.
| Graha Maitri points | Relationship | Pairs on this page | This page’s scores |
|---|---|---|---|
| 5 | Mutual friends | 1 and 2, 1 and 3, 1 and 9, 3 and 9, 5 and 6, 6 and 8 | 86 to 88 |
| 4 | Friend and neutral | 1 and 5, 2 and 3, 2 and 9, 5 and 8 | 76 to 80 |
| 3 | Both neutral | 3 and 8, 6 and 9 | 66 to 68 |
| 1 | Friend one way, enemy the other | 2 and 5 | 88 |
| 0.5 | Neutral and enemy | 2 and 6, 2 and 8, 3 and 5, 3 and 6, 5 and 9, 8 and 9 | 55 to 66 |
| 0 | Mutual enemies | 1 and 6, 1 and 8 | 55 to 58 |
For 20 of the 21 pairs of different classical planets, the chart tracks the traditional points closely: the more friendly the planets, the higher the score. The one exception is the Moon and Mercury, roots 2 and 5. It is the only pair in the classical table where one planet is a friend and the other an enemy, worth just 1 point, yet the chart gives it 88, its highest score. We have kept the score unchanged, because it is the site’s calculation, but we flag it here so you can read that result with caution.
How often each band appears
Birth days are not spread evenly across root numbers: roots 1 to 4 each collect four possible days, and the 29th, 30th and 31st do not occur in every month. Weighting every pair of birth days by how often those days occur in the calendar, this is how couples fall across the bands. It is our own calculation on the calendar, not a survey of real couples.
| Band | Share of couples |
|---|---|
| Excellent (85 to 88) | 23.0% |
| Very Good (75 to 84) | 26.0% |
| Good (65 to 74) | 22.9% |
| Moderate (55 to 64) | 28.2% |
| Challenging (below 55) | 0% |
About half of all couples score Very Good or better, and a little over a quarter land in Moderate, the lowest band that exists in practice. If your result is Moderate, you share it with more than one couple in four. One couple in nine shares the same root number, and same-root pairs always score between 78 and 84.
Agreement with our other compatibility page
Our Love Compatibility page uses a simpler favourable-number rule. The two pages give the same broad answer for every pair except three involving root 4: 1 and 4, which that page counts as favourable and this one scores 55, and 4 and 5 and 4 and 6, which this page rates Excellent or Very Good and that page does not count as favourable. Together those three pairs cover about 7.7% of couples. Every one of them involves Rahu, the planet with no classical table to settle the question.
Which Birth Days Match Yours?
First find your root number from your birth day, then see which roots this page rates Excellent and which it places in the Moderate band.
| Root (born on) | Planet | Excellent with roots | Moderate with roots |
|---|---|---|---|
| 1 (1st, 10th, 19th, 28th) | Sun | 2, 3, 9 | 4, 6, 8 |
| 2 (2nd, 11th, 20th, 29th) | Moon | 1, 5 | 4, 8 |
| 3 (3rd, 12th, 21st, 30th) | Jupiter | 1, 9 | 4, 5, 6 |
| 4 (4th, 13th, 22nd, 31st) | Rahu | 5, 8 | 1, 2, 3, 9 |
| 5 (5th, 14th, 23rd) | Mercury | 2, 4, 6 | 3, 9 |
| 6 (6th, 15th, 24th) | Venus | 5, 8 | 1, 3 |
| 7 (7th, 16th, 25th) | Ketu | None; all pairs 68 to 78 | None |
| 8 (8th, 17th, 26th) | Saturn | 4, 6 | 1, 2, 9 |
| 9 (9th, 18th, 27th) | Mars | 1, 3 | 4, 5, 8 |
A word of perspective for anyone reading this before a marriage decision. Some articles warn that marrying the “wrong” Mulank raises the risk of a marriage breaking down. There is no evidence for that, and we do not repeat it. If your family follows kundli matching, that is a separate process with its own experts; and for any couple, how two people talk, share work and handle disagreement matters far more than their birth days.
Common Misconceptions About Birth Date Compatibility
- “The month and year of birth change the result.” Not on this page. Only the day counts, so everyone born on the 14th of any month gets the same reading with a given partner.
- “A Moderate score means we are not compatible.” More than one couple in four lands there, and it is the lowest band this chart can produce.
- “A high score guarantees a happy relationship.” It describes two temperaments on paper, nothing more.
- “Every numerology site agrees on which Mulanks match.” In our comparison, no pair got the same verdict from all five sources.
- “This is the same as kundli matching.” Kundli matching compares Moon signs, nakshatras and much more; this page compares only two birth-day numbers.
- “Planetary friendships are always mutual.” Not in the classical table. The Moon counts Mercury as a friend, for example, while Mercury counts the Moon as an enemy.
- “Birth date compatibility is proven.” It is a traditional belief system, best enjoyed for reflection.
Frequently Asked Questions
How is birth date compatibility calculated?
Each person’s birth day is reduced to a single digit, the Mulank, and the two numbers are looked up in a score chart based on the friendships between their ruling planets. Born on the 14th and the 6th gives 5 and 6, Mercury and Venus, which score 86.
Does the month or year of birth matter?
Not on this calculator, which reads only the Mulank. For a reading that uses the full date of birth, try our Love Compatibility Calculator, which works from the Life Path number.
Which Mulank numbers are most compatible?
On this page, the highest scores (88) go to 1 with 2, 3 or 9; 3 with 9; and 2 with 5. The first four follow classical mutual friendships. Other sources rank pairs differently, so treat any single list as one tradition’s view.
Which Mulank numbers do not match?
The lowest scores on this page (55) go to pairs such as 1 and 8, 1 and 4, 2 and 8, 4 and 9, and 8 and 9. Even these are Moderate, not a warning, and more than a quarter of all couples fall in that band.
Why does another site say our Mulanks are incompatible?
Because sources use different friendship tables, especially for roots 4 and 7, and some compare the Bhagyank too. The comparison table above shows how five sources read the same eight pairs.
Is Mulank compatibility used in marriage matching?
Some families and numerologists look at it, but it is not part of kundli matching. The closest kundli concept is Graha Maitri, which uses the same planetary friendships but compares the lords of the partners’ Moon signs, and counts for 5 of the 36 gunas.
What if we both have the same root number?
Same-root pairs score between 78 and 84 on this page, all Very Good. Two people with the same temperament usually understand each other quickly, though they can also share the same blind spots.
Why is root 7 always in the middle?
Root 7 is ruled by Ketu, which has no entry in the classical friendship table, and the tables that exist disagree. This page gives 7 a neutral row, with every pairing between 68 and 78.
What does the percentage mean?
It is a position on this page’s own scale, which runs from 55 to 88. It is not a probability and cannot be compared with percentages from other calculators.
Does birth date compatibility really work?
There is no scientific evidence that it does. It is a traditional numerology practice that many people enjoy as a light way to talk about how two people get along.
Related Numerology Tools
These tools look at the same relationship from other angles:
- Love Compatibility Calculator: compatibility by full date of birth.
- Name Compatibility Calculator: compatibility by names.
- Mulank Calculator: your root number in depth.
- Marriage Date Numerology Calculator: check a wedding date against both birth days.
- Life Path Number (Bhagyank) Calculator: your full-birth-date number.
You can also browse all our numerology calculators in one place.
Two birth days, two planets and one score can start an interesting conversation about how two people share their days. Enjoy the reading and check the working, and remember that the small daily habits of kindness, patience and humour say far more about a partnership than any number.
This information is based on traditional numerology principles and is intended for entertainment and self-reflection, not as a substitute for professional advice. Read our full Disclaimer for more.