Terms of Service

Last updated 7 September 2026

What changed on 7 September 2026. Until this version these terms asked you to enter only your own Riot ID. The head-to-head page compares two accounts, so that rule now describes what the site offers rather than forbidding a page it ships. What is still forbidden is unchanged: tracking, profiling or monitoring a player, and compiling a record of someone they did not ask for. Head-to-head reports only games two accounts played in the same match, never anything about either of them alone.

KayLoL (kaylol.gg) is a free tool that estimates the probability that blue side wins a League of Legends draft, and publishes champion statistics derived from completed ranked games. These terms describe what you can expect from it and what it asks of you. Using the site means you accept them.

What KayLoL is

A model trained on millions of completed ranked games returns a probability, not a verdict. A draft scored at 45% still wins close to half the time, and the site is explicit about the size of its own edge: the “Does it work?” page publishes the model's measured accuracy and calibration, including the parts that are unflattering.

The champion rankings on the tier list are historical win rates for a cohort of players, not a measurement of how strong a champion is. That distinction is not a footnote, and the page states it permanently rather than in a tooltip.

What KayLoL is not

• It is not affiliated with, endorsed by, or connected to Riot Games. See the notice at the bottom of every page.
• It does not interact with the game client, read your game files, inject anything, or automate any part of playing. Everything it knows comes from Riot's public Games API and from what you type into it.
• It is not a betting or gambling service, it is not connected to one, and it must not be used to inform one.
• It is not advice. A prediction is for interest and practice, and which champion you pick is still your decision.

Using the site

Please do not:

• Automate requests against the site or its API, scrape it in bulk, or proxy it to redistribute its responses. The API runs on one small server inside Riot's rate limits, so a script that hammers it takes the site away from everyone rather than just from us.
• Republish or resell KayLoL's output as your own product, or present it as an official Riot Games source.
• Track, profile or monitor another player, or compile or publish a record of someone's play that they did not ask for. Comparing two accounts on the head-to-head page is a use the site offers: it reports only the games those two accounts played in the same match, and nothing about either of them on their own.
• Interfere with the service, probe it for vulnerabilities without telling us first, or try to reach data that the published pages do not offer.

Entering a Riot ID is optional everywhere it is offered. Every page except head-to-head is about your own account and asks for yours; head-to-head asks for two, because a comparison cannot be made from one.

No account, no payment

There is no sign-up, no login and no password, so there is no account to lose and nothing to cancel. KayLoL is free to use and there is no charge for anything on it.

If that changes, the draft predictor, the tier list and the metrics page as they exist today will remain available free of charge. Voluntary donations, sponsorship or an optional paid tier may be added to cover hosting; this page will be updated before any of them appears, and none of them will put a feature that is free today behind a payment.

An optional account, signed in through Riot, may be added later so that a player can save drafts and look back at their own predictions. It would stay optional: everything the site does today works without one, and will keep working without one.

Availability and accuracy

KayLoL is provided as is, without any warranty. There is no uptime commitment. The model is retrained as new patches land and its numbers will change: a prediction describes the games in its training data, and League changes underneath it constantly. Riot's API can be slow, rate-limited or unavailable, and parts of the site stop working when it is.

To the extent the law allows, we are not liable for any loss arising from using the site or from relying on anything it says — including lost games, lost LP, and decisions made because of a number on this page.

Your data

What the site stores, and what it deliberately never stores, is set out in the Privacy Policy. The live retention settings of the running service are published on the metrics page, read from the service itself rather than described from memory.

Riot Games

KayLoL uses the Riot Games API under Riot's API Terms of Use and developer policies. Champion names, images and other game assets belong to Riot Games and are used through Riot's published developer assets. Your use of League of Legends itself is governed by Riot's Terms of Service, not by this page.

Changes and contact

These terms will change as the site does. The date at the top is the date of the last change, and a material change will be noted on the site rather than made quietly.

Questions, corrections, takedown requests and data-deletion requests all go to the same place: contact@kaylol.gg.