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CelestiaYour cosmic guide

Pythagorean vs Chaldean Numerology: What's the Difference?

· 5 min read

There are two main systems for turning the letters of a name into numbers: Pythagorean and Chaldean. They often give different results for the same name — so it helps to know how each works.

Pythagorean numerology

Named after the Greek mathematician Pythagoras, this is the most common system in the West. Letters are numbered 1 to 9 in alphabetical order, then the pattern repeats.

123456789
ABCDEFGHI
JKLMNOPQR
STUVWXYZ

It is simple, easy to remember, and usually applied to your full birth name.

Chaldean numerology

Chaldean numerology comes from ancient Babylon and is especially popular in India. Letters are grouped by their sound vibration, using only the numbers 1 to 8. The number 9 is considered sacred and is not assigned to any letter.

12345678
A I J Q YB K RC G L SD M TE H N XU V WO ZF P

Chaldean numerologists usually look at the name you are commonly known by, and pay close attention to the compound number (the total before reducing to a single digit).

Key differences

PythagoreanChaldean
OriginAncient GreeceAncient Babylon
Numbers used1–91–8
Letter orderAlphabeticalBy sound
Name usedFull birth nameName you use day to day
Compound numbersLess emphasisVery important

Which one should you use?

Neither is "right". Many people find the Pythagorean system easier to start with, while Chaldean is often preferred for name corrections and business names.

Try both with our free name number calculator — switch the system with one click and compare.