Pythagorean vs Chaldean Numerology: Differences, Charts and a Worked Example

Key takeaways

• There are two main systems for letter numerology: Pythagorean, the most widespread in the US and Europe, and Chaldean, popularized by Cheiro in the early 20th century.

• They use different charts, so the same name gives different results: "Emma Clark" is a 5 in Pythagorean and a 7 in Chaldean.

• Chaldean numerology never assigns 9 to a letter and often uses the name you go by.

• Both labels are largely modern: neither Pythagoras nor the Chaldeans of Babylon left these charts behind.

Two Systems, Two Logics

Pythagorean Numerology

It assigns 1 to 9 to letters in alphabetical order, starting over every nine letters. It's the system used in every article on this site.

• 1 · 2 · 3 · 4 · 5 · 6 · 7 · 8 · 9

• A, J, S · B, K, T · C, L, U · D, M, V · E, N, W · F, O, X · G, P, Y · H, Q, Z · I, R

Chaldean Numerology

It assigns numbers according to a logic described as vibrational or sound-based, not alphabetical. It only uses 1 to 8: 9 is considered sacred and isn't given to any letter.

• 1 · 2 · 3 · 4 · 5 · 6 · 7 · 8

• A, I, J, Q, Y · B, K, R · C, G, L, S · D, M, T · E, H, N, X · U, V, W · O, Z · F, P

Same Name, Two Results

Example: Emma Clark (fictional name)

• Letter · E · M · M · A · C · L · A · R · K · Total

• Pythagorean · 5 · 4 · 4 · 1 · 3 · 3 · 1 · 9 · 2 · 32 → 5

• Chaldean · 5 · 4 · 4 · 1 · 3 · 3 · 1 · 2 · 2 · 25 → 7

The same name gives an expression number of 5 in one system and 7 in the other. It's the clearest illustration that these aren't objective measurements but two different conventions.

Other Method Differences

• Chart · Alphabetical, 1 to 9 · Non-alphabetical, 1 to 8

• Name used · Full birth name · Often the name you're known by

• Compound numbers · Reduced (except master numbers) · The compound number before reduction (10 to 52) is often interpreted in its own right

• Where it's used · Dominant in North America and Europe · More common in India and among some English-speaking practitioners

Where Do These Names Come From?

"Pythagorean": Pythagoras and his school (6th century BCE) gave numbers great philosophical weight, but this letter chart isn't theirs. The link is mostly retrospective, and today's method took shape in the early 20th century.

"Chaldean": the Chaldeans were a people of Mesopotamia, and in Europe the word long served as shorthand for Babylonian astrologers. No ancient source documents this chart as Babylonian. The system was mainly spread by Cheiro (Louis Hamon), an Irish palmist and numerologist famous in the early 20th century. He's also the source of the number-planet pairings cited in our articles (1 Sun, 2 Moon, 3 Jupiter, 4 Uranus, 5 Mercury, 6 Venus, 7 Neptune, 8 Saturn, 9 Mars).

Which One Should You Use?

Neither is "truer" than the other: numerology has no scientific validation in any system. The choice is about consistency:

• stick to one system for all your calculations, without mixing charts;

• use your source's system: a Pythagorean book or report should be read with the Pythagorean chart;

• compare out of curiosity, keeping in mind that the divergence itself is instructive.

The life path number, calculated from your birth date, doesn't depend on any letter chart: it's identical in both systems.

What Numerology Can and Cannot Tell You

The fact that one name gives 5 or 7 depending on the chart is a reminder that these numbers are conventions. They can feed reflection, as long as they aren't taken as a measure of personality.

Frequently asked questions