Dating Calculator
Dating calculator works out Compatibility score and Verdict from First name, Second name and First birth date. The default figures on this page give compatibility score of 18.18 %; change any entry and the result, the working and the sources update together.
Your figures
Updates as you typeHow this is worked out
5 steps
- Reduce the names to letters: "Romeo" -> romeo (5), "Juliet" -> juliet (6).
- Letters held in common (multiset intersection) = 1.
- Dice similarity = 2 x 1 / (5 + 6) = 0.181818 = 18.18%.
- Cancelling the shared letters leaves 5 - 1 + 6 - 1 = 9 letters.
- Counting out F, L, A, M, E, S 9 at a time leaves "E" = Enemy.
Its 4 worked examples are re-run on every release, last on 15 September 2026. What changed
Sources and references
5 sources
What the dating calculator calculates
Scores two names for entertainment using the Sorensen-Dice letter-similarity coefficient, plays the FLAMES counting game on the leftover letters, and reports numerology life path numbers and time together when birth dates are supplied.
How to use this dating calculator
Enter First name, Second name, First birth date and Second birth date. Compatibility score updates as you type, and “Use a worked example” loads checked figures you can adjust. Change one figure at a time to see what drives the result.
How the result is worked out
Open “How this is worked out” beside the result for the step-by-step calculation behind Compatibility score, Verdict and FLAMES result.
The method follows Dice, L. R. "Measures of the Amount of Ecologic Association Between Species", Ecology 26(3), 297-302 - the 2|A n B|/(|A|+|B|) similarity coefficient, Sorensen-Dice coefficient definition, Josephus problem - the counting-out elimination used by the FLAMES game, FLAMES relationship game - rules for cancelling shared letters and counting out F, L, A, M, E, S and Pythagorean numerology life path number - digit sum of the birth date reduced to a single digit, with master numbers 11, 22 and 33 retained.
Romeo and Juliet example
With First name: Romeo, Second name: Juliet, the calculator returns Letters in the first name: 5, Letters in the second name: 6, Letters the names share: 1. This example is checked against an independent source in the test suite.
What you can compare
Change one input at a time to see how it affects Compatibility score, Verdict and FLAMES result. The inputs you can vary are First name, Second name, First birth date, Second birth date, Date you got together and Count time together up to.
Understanding Compatibility score, Verdict and FLAMES result
For entertainment only. This has no scientific, psychological or predictive validity and must not be used to make decisions about a real relationship.
Results are general information, not financial, tax, legal, medical or engineering advice. Check any decision that matters with a qualified professional.
See something wrong? Report a problem with this calculator
Frequently asked questions
What is the 3 6 9 rule for dating?
On the figures this page opens with, the compatibility score is 18.18%. No single number fits everyone: it follows First name, Second name and First birth date, so enter your own above and the answer updates as you type.
What is the 3-3-3 rule for dating?
It needs First name, Second name, First birth date, Second birth date, Date you got together and Count time together up to. Nothing else is required, and the figures stay in your browser.
What is the 2 2 2 love rule?
The result gives Compatibility score, Verdict, FLAMES result, Surviving FLAMES letter, Letters the names share and Letters in the first name, each labelled with its unit so the figure can be read on its own.
Can you get 100% on love calculator?
Scores two names for entertainment using the Sorensen-Dice letter-similarity coefficient, plays the FLAMES counting game on the leftover letters. Put your own figures in above and the working updates beside the result. For scale, the default figures on this page give 18.18 %.
What information do I need for the dating calculator?
You need First name, Second name, First birth date, Second birth date, Date you got together and Count time together up to. The page opens with default figures that give compatibility score of 18.18 %, so you can see the scale before entering your own.
What does this dating calculator show?
It shows Compatibility score, Verdict, FLAMES result, Surviving FLAMES letter, Letters the names share, Letters in the first name, Letters in the second name and Letters left after cancelling, with the working and any warnings for your entries.