Pythagorean or Chaldean: Two Charts, One Name, Two Numbers

One chart is a pattern, the other is a list

The Pythagorean chart can be written as a single line of arithmetic: take the letter's position in the alphabet, subtract one, take the remainder on division by nine, add one. Nothing needs to be memorised. Every value from 1 to 8 gets exactly three letters and 9 gets only two, I and R, because twenty-six does not divide by nine.

The Chaldean chart obeys no such rule and has to be looked up. Its rows are lopsided — five letters on 1, only two on 7 and two on 8 — and 9 is empty by design. That single hole is what pulls the two systems apart on almost every name: I and R carry 9 in one chart and 1 and 2 in the other, and R is one of the commonest consonants in all six of the languages this site publishes in.

The arithmetic consequence is visible in the totals. Because Chaldean values are capped at 8 and skip 9 entirely, the Chaldean sum comes out lower than the Pythagorean one for 90 % of the corpus. Albert Einstein is a clean example: 63 against 46 for the same fourteen letters.

The bigger variable is not the chart, it is the name

Marie Curie signed her work under more than one name, and each form gives a different number. Her birth name, Maria Salomea Skłodowska, is 76 and reduces to 4 in the Pythagorean chart. Marie Skłodowska Curie is 88 and reduces to 7. Plain Marie Curie is 57 and reduces to 3. Three real forms of one real name, three answers, before either chart has been argued about. The Chaldean readings of the same three are 8, 5 and 3, and the only place the two systems meet is the shortest form.

This is why every book insists on one particular form — usually the full name as written on the birth record — and why the instruction matters more than the chart. The calculator here does not enforce it, because it cannot know what is on your certificate, but it does normalise what you type: accents are stripped before the letters are valued, so Sofía Ramírez and SOFIA RAMIREZ give the same total, and letters with no plain equivalent are expanded — Ø becomes O, Æ becomes AE, Þ becomes TH, ß becomes SS. Hyphens and spaces are ignored, so Marie Skłodowska-Curie and Marie Skłodowska Curie are the same 88.

What the reserved nine does and does not do

The Chaldean rule is stated as a prohibition on letters, and it is often repeated as though it made 9 unreachable. It does not. The letters are capped, the totals are not: a name whose Chaldean letters add to 45 reduces to 9 like any other multiple of nine. Across the 1,200-name corpus the Chaldean route lands on 9 for 12.9 % of names and the Pythagorean route for 10.8 %, so the chart that forbids 9 produces it slightly more often.

The same corpus shows the Chaldean chart handing out master numbers a little more freely as well: 14.3 % of names stop on 11, 22 or 33 against 11.6 % under the Pythagorean chart. Neither figure is a doctrine. They are what falls out of two irregular tables applied to the given names and surnames people in these six countries actually carry.

Frequently asked questions

Which chart should I use?

Pick one and say which. The Pythagorean chart is far more common in modern books and is what almost every free calculator uses without saying so; the Chaldean chart is the older-sounding one and the one Cheiro popularised. Since they agree on barely a tenth of names, a reading that does not name its chart is not reproducible. The calculator here prints both for exactly that reason.

Should I use my married name or my birth name?

The books say the full birth name for the expression and soul-urge numbers, and allow a current or professional name as a second, separate reading. They are different numbers about different things rather than a right and a wrong answer — Marie Curie gives 4 as Maria Salomea Skłodowska and 3 as Marie Curie. If you calculate both, label both.

What happens to accents, ß and letters like Ø?

Accents are removed before any letter is valued, so é counts as E and ñ as N. Letters that have no accented form to strip are expanded to the letters they stand for: Ø gives O, Æ gives AE, Œ gives OE, Ð and Đ give D, Ł gives L, Þ gives TH and ß gives SS. Weiß is therefore read as WEISS and Þóra as THORA. Anything that is not a letter — spaces, hyphens, apostrophes, full stops after initials — is discarded.

Does a middle name or an initial change the result?

Almost always. Every letter you add or remove moves the total, and only a change that happens to be a multiple of nine leaves the reduced number where it was. Writing A. Einstein instead of Albert Einstein drops twenty-one from the Pythagorean total and takes the answer from 9 to 6. Decide on a form before you calculate, not after you see the number.