Try it
Calculation runs locally in this page. Nothing you enter here is sent anywhere or saved.
- Win probability going in:
- Rating change:
- New rating:
What this calculator is (and isn't)
This is a generic Elo-style rating simulator, built from the same publicly documented formula chess federations have used for decades — not a copy of Omoggle's own scoring or matchmaking code:
- Omoggle has never published its exact ELO formula, starting value, or K-factor, so any specific weighting beyond the general shape is community description, not a confirmed specification. See how Omoggle's ELO rating works for that distinction in full.
- This tool exists to make the general mechanic tangible — how a "surprising" win against a higher-rated opponent moves a number more than a win against an equal — not to predict a specific live result.
- It does not connect to, scrape, or read from Omoggle or any other platform. Every number here is typed in by you and calculated in your browser.
The math behind it
The standard Elo formula has two steps:
- Expected score:
1 / (1 + 10^((opponent − you) / 400))— a probability between 0 and 1 for how likely you were expected to win, based purely on the rating gap. - Rating change:
K × (actual − expected)— where actual is 1 for a win, 0.5 for a draw, or 0 for a loss, and K is the K-factor above.
Beating a much higher-rated opponent produces a bigger jump than beating someone rated near you, because the expected-score term was already low; the reverse is true for a loss against a weaker opponent.
A rating shift is not a score, and neither guarantees the other
An Elo-style rating and Mogalytics' own composite score answer different questions — see Molecule to Slayer, explained for how a tier maps to one scan, and how Omoggle's scoring actually works for the six-measurement mechanics behind it. A high composite reading on one scan does not by itself guarantee a high rating, since a rating only moves through head-to-head outcomes over many duels.
Nothing on this page or anywhere on Mogalytics guarantees a specific rating, score, or win on a live third-party service.
Related reads
- How does Omoggle's ELO rating work? — the full explainer this calculator is a companion to.
- Molecule to Slayer, explained — what each tier band means.
- How to improve your Omoggle score — the two testable levers behind a composite reading.
- The practice test checklist — what to run through right before going live.