Numerology has no governing body, no standard, and several schools that quietly contradict each other. Any calculator therefore has to make choices, and most make them silently. This page is the list of ours: what the engine behind every result on this site does, and — more usefully — every point at which it will disagree with a calculator somewhere else.
It is a page about our conventions. If what you want is instruction, the guide to calculating a chart by hand takes one example through all six numbers step by step, and is the better place to start.
Letters to numbers
Every calculation here uses the Pythagorean table: A=1 through I=9, then J=1 through R=9, then S=1 through Z=8. Positions, not sounds. You can check any letter without a table by counting its place in the alphabet and reducing it all the way to a single digit — R is the eighteenth letter, 18 reduces to 9, R is 9. Letters always reduce fully: the master-number exception below applies to totals, so K is 2 and V is 4 rather than 11 and 22.
The main alternative is the Chaldean table, which groups letters by sound and never assigns 9 to any of them. It produces different numbers from the same name. We use Pythagorean throughout, and compare the two systems on one name rather than presenting either as the correct one.
Reducing, and where we stop
Multi-digit totals are reduced by adding their digits until one remains. The reduction stops early on 11, 22 and 33 — the master numbers — and on nothing else.
There is a genuine disagreement here, and we are on the more inclusive side of it. We hold a master number wherever it appears in a reduction chain, not only as a final total — including at the component stage of a Life Path. A birth year of 1993 reduces to 22 and stops there rather than continuing to 4, so it contributes 22 to the sum.
The effect can be large rather than marginal. Someone born on 15 May 1993 has a Life Path of 33 here, and a 6 on a calculator that reduces the year all the way down. That is not a rounding difference, it is a different number, and it is the single biggest reason a result here may not match one elsewhere.
The six core numbers
- Life Path — from your date of birth. We reduce the month, day and year separately, then add the three results and reduce again.
- Expression — from every letter of your full birth name.
- Soul Urge — from the vowels of that name.
- Personality — from the consonants.
- Birthday — the day of the month you were born, reduced.
- Maturity — Life Path and Expression added, then reduced.
What each is taken to mean is on the core numbers, and how they are read against one another is on how to read your chart.
The letter Y
Y is treated as a vowel unless it sits directly beside one of a, e, i, o or u. So it is a vowel in Lynn and Mary, and a consonant in Maya, where the neighbouring a already carries the vowel.
That is a positional heuristic about spelling. It is not a claim about pronunciation, and it will occasionally disagree with your ear — a rule that actually followed the vowel sound would need to know how you say your own name, which no calculator does. Because Soul Urge and Personality are built from small letter counts, a Y is the single letter most likely to move both.
Karmic debt
A total of 13, 14, 16 or 19 reached at any step before the final reduction is flagged as a karmic debt. Not only when the raw total is one of the four: a name summing to 94, reducing 94 → 13 → 4, carries a 13 even though 94 is not itself a debt number.
This interacts with the Life Path convention above. Because we reduce month, day and year separately, a debt can appear here that a single-pass digit sum of the whole date would walk straight past. The arithmetic is printed beside every result, so you can always see exactly where a 13, 14, 16 or 19 turned up.
Cycles reduce all the way
Personal year, month and day are periods rather than identities, and master numbers are not held in them — a personal year is always 1 to 9. The same applies to the month, day and year components that feed the pinnacles and challenges: those are reduced to single digits first, which is what keeps the two sets consistent with each other. Pinnacle totals can still be master numbers; challenges never can, because they are absolute differences and always land between 0 and 8.
One consequence is worth naming, because it looks like an error otherwise. The third pinnacle adds the single-digit roots of the first two, so a chart with two master pinnacles shows something like "(11 → 2) + (11 → 2) = 4". The reduction is printed rather than hidden, so the 4 can be traced.
Karmic lessons
Karmic lessons are the values from 1 to 9 that no letter of the full birth name carries. They are about absence, where karmic debt is about a total — the shared word is the only thing the two have in common, and it causes more confusion than anything else in the vocabulary.
Where we knowingly differ
If a figure here disagrees with one elsewhere, it is almost certainly one of these six, and almost never an arithmetic mistake on either side:
- Month, day and year are reduced separately before being added.
- Master numbers are held at any step of a reduction, including a birth year — so 1993 contributes 22 to a Life Path rather than 4.
- Karmic debt is flagged at any stage of a reduction, not only on the raw total.
- The Y rule is positional rather than phonetic.
- Cycle numbers reduce fully, so no personal year is ever an 11.
- The third pinnacle adds the reduced roots of the first two.
None of these is a secret and none is settled. Where a method is contested we say so rather than presenting one option as the truth.
What the engine does not do
The numbers are computed by deterministic code with no language model anywhere near them — the arithmetic is the one part of numerology that is either right or wrong, and it is tested rather than generated. Interpretations are written and edited in-house, not produced at runtime, and they are not attributed to invented experts. Our editorial policy covers that in full.
If a definition here is unfamiliar, the glossary has it in forty words. And if something on this page looks wrong, we would rather fix it than defend it — tell us.