Numerology
Chaldean vs Pythagorean numerology
The two letter-value systems give different numbers for the same name. What each one is, where it came from, which one this site uses where, and how to tell which a practitioner is quoting.
Two systems assign values to letters, and they disagree. A name that is a 7 in one is frequently a 3 in the other — so a number quoted without naming its system tells you less than it appears to.
Pythagorean: the alphabetical one
A=1, B=2, C=3, and so on to I=9; then J returns to 1 and the cycle repeats twice more. It is the system almost every English-language numerology site uses, and it is the one behind the personal tools on this site.
Its logic is positional: the letter's place in the alphabet decides its value. This is simple and easy to check, which is much of why it spread — and it is also the reason critics point out that it depends entirely on the Roman alphabet, which the Greeks it is named after did not use.
Chaldean: the older, sound-based one
Chaldean assigns values by sound rather than position, and its table is irregular: A, I, J, Q and Y are all 1; B, K and R are 2; C, G, L and S are 3, and so on to F and P at 8.
It stops at 8. There is no letter worth 9 in the Chaldean system, because 9 is treated as sacred and not attached to any sound. That single quirk is the easiest way to identify which system a practitioner is using: if any letter is worth 9, it is Pythagorean.
- 1 — A, I, J, Q, Y
- 2 — B, K, R
- 3 — C, G, L, S
- 4 — D, M, T
- 5 — E, H, N, X
- 6 — U, V, W
- 7 — O, Z
- 8 — F, P
Which one should you use?
Convention rather than proof decides this. Business and brand numerology conventionally uses Chaldean, and the business checker on this site leads with it. Personal name numerology in the English-speaking world conventionally uses Pythagorean, which is what the name checker and the full report use.
Indian practitioners use both, often within the same consultation, and a good one will tell you which they applied. The honest position is that neither system has evidence behind it that the other lacks — they are two conventions, and the useful discipline is simply to be consistent and to say which one you used.
Why it matters more than it sounds
Because people make decisions on the answer. Someone paying for a name correction to reach a 6 should know that the target is 6 in one system and something else in the other, and that a practitioner who will not name their system cannot be checked.