Numerology apps can give different life path numbers when they add up the same birth date in different ways. Below are two possible ways to add a full date, which give 11 and 2 for one sample date, and one input error, a two-digit year, which gives 1.
What are the different ways to add up a birth date?
One way adds all eight digits at once. A second reduces the month, the day and the year to one digit each, then adds those three. Both are possible conventions. Adding all at once, NinePath keeps a total that lands on 11, 22 or 33. In the parts-first way shown here, each part is reduced to one digit first, and a final total that lands on 11, 22 or 33 is kept.
Leaving out the century digits is not a third way. When a method asks for the year as four digits (YYYY), a two-digit year is an input error. The last row of the table shows its effect only as an illustration.
| Way of adding | Working | Result |
|---|---|---|
| All eight digits at once | 0 + 7 + 0 + 8 + 1 + 9 + 8 + 5 = 38, then 3 + 8 = 11 | 11 |
| Month, day and year first | 8 + 7 + 5 = 20, then 2 + 0 = 2 | 2 |
| Two-digit year (input error) | 0 + 7 + 0 + 8 + 8 + 5 = 28, then 10, then 1 | 1 |
- M8
- D7
- Y1
- Y9
- Y8
- Y5
Year: 1 + 9 + 8 + 5 = 23, then 2 + 3 = 5. Then 8 + 7 + 5 = 20, then 2 + 0 = 2.
Added in parts, this date gives 2, while adding all eight digits at once stops at 11.
The parts-first way goes back at least to 1926. Ariel Yvon Taylor's Numerology Made Plain (Taylor, 1926) works a birth date out from the digit of each part (page 56).
Had the above birth date been September 4, in a year which totaled 7, we would have had the digits 9-4-7, totaling 20 or 2.
Why do the two ways end on the same single digit?
Adding digits always ends on the remainder after dividing by 9 (or 9 when the remainder is 0), in any order. So adding all at once and adding in parts reach the same single digit. They differ only when one of them stops at 11, 22 or 33 and the other passes it. For birth years 1900 to 2099, that happens on about 15% of dates (NinePath count: 11,123 of the 73,049 dates from 1900 to 2099).
A two-digit year is different: it's an input error, not a way of adding. It leaves out the 19 or the 20, so the total changes, not only the order. For birth years 1900 to 1999 its single digit is always one step lower on the 1-to-9 cycle (after 1 comes 9), and for 2000 to 2099 two steps lower.
Which way does NinePath use?
To find your life path number, add all eight digits of your birth date, then add the digits of the total until one digit is left. If a step lands on 11, 22 or 33, NinePath keeps it as a master number. The steps are in how to calculate your life path number.
Neither full-date way is a mistake in its own arithmetic. Each follows its own rule, so pick one and use it every time. A two-digit year is not a choice of method: enter all four digits of the year whenever a method asks for them.
What this means for your day
For your day
Do
Find out how a calculator adds your date before you compare its number.
Don't
Don't switch methods to get a number you like better.
Questions people ask
Why does one app say 11 and another say 2?
11 reduces to 1 + 1 = 2. One way stopped at 11 and the other went past it, so both point to the same single digit.
Which life path calculation should I use?
Both full-date ways are consistent with their own rules, so the arithmetic can't choose between them. Pick one and use it every time, and always enter all four digits of the year.
Sources
- Ariel Yvon Taylor, Numerology Made Plain (Laird & Lee, Chicago, 1926), Library of Congress copy on archive.org. Page 56: a birth date worked out from the digits of month, day and year, "9-4-7, totaling 20 or 2".
- Wikipedia: Digital root. Repeated digit sums equal the remainder after dividing by 9 (or 9 when the remainder is 0), whatever the order of adding.