Most name calculators use one of two letter tables and rarely say which. The tables look similar enough that the same name can produce two plausible but different answers. Putting both charts in one place makes the difference inspectable instead of mysterious.
Both charts in one table
The Pythagorean chart assigns every value from 1 to 9 and cycles through the alphabet; the Chaldean chart stops at 8. The letter assignments are not a modern rounding of one another — several letters move by three or more points, and I and J share a value in Chaldean while they sit in different Pythagorean groups.
| Value | Pythagorean | Chaldean |
|---|---|---|
| 1 | A J S | A I J Q Y |
| 2 | B K T | B K R |
| 3 | C L U | C G L S |
| 4 | D M V | D M T |
| 5 | E N W | E H N X |
| 6 | F O X | U V W |
| 7 | G P Y | O Z |
| 8 | H Q Z | F P |
| 9 | I R | — |
The Pythagorean values are listed in Taylor's 1926 handbook under each digit (Taylor 1926 pp. 21–22), and Cafe Astrology prints the same chart (Cafe Astrology, Numerology). Cheiro gives the Chaldean table on page 70 of his handbook and explains the missing 9 as reserved, so no letter carries it (Cheiro 1926 pp. 70–71).
One name, both systems
David Wark Griffith is a useful test because the 1926 handbook already worked him out and because both charts give a clean result. Under the Pythagorean chart the name yields three numbers; under the Chaldean chart it yields one. The raw sums differ before any reduction, which is the point.
| Number | Raw sum | Result |
|---|---|---|
| Pythagorean Expression (all letters) | 95 | 5 |
| Pythagorean Soul Urge (vowels) | 29 | 11 |
| Pythagorean Personality (consonants) | 66 | 3 |
| Chaldean name number | 59 | 5 |
Taylor's own chart prints 22-8-11 for the three name parts and gives 11 for the vowel sum (Taylor 1926 p. 23). The Chaldean sum of 59 reduces to 14 and then 5, with no master stop: Cheiro's system treats a compound 22 as 4, so a 22 in the middle of a Chaldean calculation is never kept (Cheiro 1926 p. 71).
Where the letters move
The largest jump is I: 9 in Pythagorean, 1 in Chaldean. Q and R also fall by seven, while F rises from 6 to 8. B, C, D and E keep the same value in both charts, and A and J are unchanged. The per-letter table on the calculator's result page shows both values in every cell, so you do not have to convert a name by hand to see where a total came from.
| Letter | Pythagorean | Chaldean |
|---|---|---|
| F | 6 | 8 |
| G | 7 | 3 |
| H | 8 | 5 |
| I | 9 | 1 |
| O | 6 | 7 |
| P | 7 | 8 |
| Q | 8 | 1 |
| R | 9 | 2 |
| S | 1 | 3 |
| T | 2 | 4 |
| U | 3 | 6 |
| V | 4 | 6 |
| W | 5 | 6 |
| X | 6 | 5 |
| Y | 7 | 1 |
| Z | 8 | 7 |
Which name, and which tradition
The two systems also differ in which name they expect. Cheiro says the "most used Christian and Surname" gives the key number (Cheiro 1926 p. 71), while the Pythagorean procedure in Taylor uses the original full name. Numerara uses the birth name for both, so the comparison above stays like with like; for someone known by a different name, Cheiro's rule would give another number.
A Chaldean result is one number, not a trio. Cheiro does not split vowels from consonants, and this site does not invent a Chaldean Soul Urge to fill a card. If you want three name numbers, the Pythagorean chart provides them; the Chaldean number stands beside them as a single older reading.
Choosing a chart
Neither chart is more accurate in any measurable sense; they are different traditions with different letter assignments. The useful question is which one your source uses, because a calculator that silently switches charts will look wrong even when its arithmetic is right. Both values are shown together here so the switch is visible, and Why calculators disagree runs the same comparison across the other rule branches.