About
Why this site exists
Bookmakers offer odds but never display what those odds actually give back to players.
That share is called the RTP — Return To Player. It can be computed from the odds themselves, in three operations, yet it remains invisible to the vast majority of bettors. The consequence: many bettors amplify their losses by staking on bets with a very unfavourable RTP.
RTP Calculator was built to serve one very simple function: computing the Return To Player rate of sports bets, so that every bettor can act knowingly.
Who publishes this site
This site and the associated Android app are designed, developed and funded by an independent developer operating as a sole trader.
The site is not affiliated with any betting operator.
How we calculate
Every figure published on this site and produced by the app rests on a single formula, verifiable by anyone:
Every odd — decimal, fractional or American — is converted into an implied probability: probability = 1 ÷ odd.
The implied probabilities of all outcomes of the market are added up. The total always exceeds 100%: that excess is the margin.
The return rate follows from the total: RTP = 100 ÷ total × 100, and margin = 100 − RTP.
The examples published in the guides are all computed with this method and can be redone by hand. The app and the online calculator apply exactly the same logic, with no intermediate rounding.
The odds used in the examples are illustrative: they demonstrate a method, they do not represent any operator's current offer.
What this site does not do
Neither the site nor the app aims to publish betting tips or tipster content.
Concretely:
- No tips, no selections, no betting advice on this site.
- No bookmaker rankings, no operator comparisons. We explain a comparison method; you apply it to the operators of your choice.
- No affiliate links, no commercial partnership with a betting operator. No payment depends on you signing up anywhere.
- No promise of profit. Knowing a bet's RTP does not make it a winner: it only tells you what it costs.
How the project is funded
The Android app is free and displays a single banner ad. The online calculator is free too and requires no sign-up. Banner ads, kept as unobtrusive as possible, may in time be added there as well to cover the project's infrastructure costs (domain, hosting, etc.).
Your data
The online calculator stores your analyses in your browser only — they are never sent to a server. The Android app keeps your history locally on your phone. Audience measurement is enabled only with your consent, which you can change at any time. The details are in our privacy policy.
Updates
The guides are reviewed and expanded regularly, and new articles are published over time. Every page shows its publication date.
Contact us
An error, an imprecision, a topic suggestion? Write to contact@rtpcalculator.com — every remark and observation is welcome.
Responsible gambling
This site offers an analysis tool, not an incentive to gamble. Sports betting carries a risk of financial loss and addiction. It is forbidden to minors. If gambling becomes a problem for you or someone close to you, seek support from a dedicated helpline in your country.