This page sets out exactly how every number on this site is calculated, which sources the rules come from, and where the tradition is ambiguous enough that we have had to choose a convention.
Letter values
Chaldean. Values 1 to 8, assigned by sound. No letter carries the value 9, which the tradition treats as sacred and reserves for totals. The full chart.
Pythagorean. Values 1 to 9 assigned by alphabetical position, cycling A=1 through I=9 and repeating.
Both charts are reproduced in full on the calculation page rather than hidden inside the tool, so any result here can be checked by hand.
Reduction rules
A compound total is reduced by adding its digits repeatedly until one digit remains.
Master numbers 11, 22 and 33 are not reduced. If any stage of reduction produces one of them, reduction stops there. This is why a name totalling 29 reduces to 11 and stops, rather than continuing to 2.
For planetary compatibility, master numbers are read through their base energy — 11 through 2, 22 through 4, 33 through 6 — because the friendship table is defined for single digits only.
What is stripped before calculating
Legal suffixes — Pvt Ltd, Private Limited, LLP, Inc, Co, Corporation and similar — are removed. They are registration formalities rather than part of the name in commercial use.
Spaces, punctuation, hyphens and ampersands are ignored. Only letters carry values.
Compound number groups
Favourable: 19, 21, 23, 24, 25, 27, 37, 41, 51. Warning: 13, 16, 18, 26, 29. Master: 11, 22, 33. Neutral: everything else.
These groups follow the classical Chaldean sources. Compounds above 51 have no individual traditional meanings, and we do not invent any — above that point the reading falls back to the single digit. The full table.
Planetary rulers and friendships
Numbers map to planets as: 1 Sun, 2 Moon, 3 Jupiter, 4 Rahu, 5 Mercury, 6 Venus, 7 Ketu, 8 Saturn, 9 Mars.
The friendship table used across every compatibility calculation on this site is fixed and published in full on the Vedic numerology page. The same table drives the name-owner check, the partner check, and the mobile and GST readings, so results never contradict each other between tools.
Friendship is not always mutual. Where one planet regards another as a friend and the reverse is not true, the reading returns "one-sided" rather than averaging the two.
Owner numbers
Life Path — every digit of the date of birth added and reduced. Birth Number — the day of the month reduced. Personal Year — birth day and month combined with the current calendar year. Personal Month and Day — the Personal Year combined with the month, then the date.
Birth time is not used. Numerology works from the date; birth time belongs to astrology.
The Lo Shu grid
The business grid is built from the Chaldean digits of the name's letters. The owner grid is built from the date of birth in the classical way.
We state plainly that the name-based grid is an adaptation — the classical Lo Shu grid is a date-of-birth construction. Both are shown, and where the same number is missing from both, that gap is flagged as needing attention. Grid details.
Where the tradition is genuinely ambiguous
Four points where sources disagree, and what we do:
Numerals inside a business name. No agreed rule. We calculate on letters only.
Which spelling to use for non-English names. No Chaldean table exists for Indian scripts. We use English transliteration, and we say so. Detail here.
Whether to include the legal suffix. Most sources exclude it. We exclude it.
Compounds above 51. The classical sources stop. We do not extrapolate.
Naming these openly matters more than resolving them. A site that presents every rule as settled is misrepresenting the tradition it is drawing on.
What we do not do
We do not predict revenue, growth or outcomes.
We do not give timelines. No numerological method establishes when anything will happen, and sources that offer timelines are inventing them.
We do not claim scientific validity. Numerology has not demonstrated predictive power under controlled conditions, and this site treats it as a traditional interpretive framework used alongside business judgement, never instead of it.
Corrections
If you find a calculation on this site that contradicts the method described here, it is an error and we want to know. The rules above are the specification the calculators are built to.
Written and reviewed by Praveen Ravichandran.