Side-by-side comparison
| Feature | Pythagorean | Chaldean |
|---|---|---|
| Letter values | 1–9, in alphabetical order | 1–8, grouped by sound |
| The number 9 | Used (I, R) | Not given to any letter |
| Which name | Full birth name | Name you use now |
| Special numbers | Master numbers 11, 22, 33 | Compound numbers 10–52 |
| Popular with | Western readers and books | Indian practitioners and name consultants |
| Modern source | L. Dow Balliett (early 1900s) | Cheiro (1920s) |
Letters that change value
| Letter | Pythagorean | Chaldean |
|---|---|---|
| F | 6 | 8 |
| I | 9 | 1 |
| O | 6 | 7 |
| R | 9 | 2 |
| S | 1 | 3 |
| Y | 7 | 1 |
Same name, two systems
Maria Lopez
- Pythagorean: 24 + 29 = 53 → 5 + 3 = 8
- Chaldean: 9 + 30 = 39 → 3 + 9 = 12 → 1 + 2 = 3
Pythagorean 8, Chaldean 3 (compound 39)
Neither result is the "real" one. They come from different traditions, so read each with its own system’s descriptions. You can check both with the Pythagorean calculator and the Chaldean calculator.
Which should you use?
- Use Pythagorean for a full personal chart with Life Path, Expression, Soul Urge and Personality numbers.
- Use Chaldean for the name you use every day, a new name, or a business name.
- If you are following a particular book or practitioner, use the system they use so that the meanings match.
Frequently asked questions
Is Chaldean numerology more accurate than Pythagorean?
Neither has been shown to be accurate in a scientific sense. Chaldean is often described as older, but the evidence shows both systems in their current form date from the early 20th century.
Can I mix the two systems?
It is best not to: each system’s number meanings were written for its own letter table.