How to Use a Betting Calculator: Worked Examples
A betting calculator converts odds and stake into a return figure, and converts prices into implied probability. Most Canadian sportsbooks build one into the bet slip, but doing the arithmetic yourself is how you learn to spot a bad price before you take it.
What does a betting calculator do?
It performs three conversions: stake and odds into return, odds into implied probability, and multiple selections into a combined price. Everything else a calculator offers is a variation on those three functions.
The return calculation is the one most people use and the least important. Your sportsbook does it automatically.
The probability conversion is the valuable one, because it turns an unfamiliar number into a question you can answer from knowledge rather than intuition.
The combination function matters for multi bets, where compounding is easy to underestimate.
How do you calculate a return by hand?
With decimal odds, multiply your stake by the price for the total return. With positive American odds, divide by 100 and multiply by stake for profit. With negative American odds, divide 100 by the number and multiply by stake.
Decimal is easiest because one multiplication gives the total return directly, which is why many experienced Canadian bettors switch their display to it regardless of the sport.
| Odds | Stake | Calculation | Profit | Total return |
|---|---|---|---|---|
| 2.50 decimal | C$40 | 40 x 2.50 | C$60 | C$100 |
| +250 | C$40 | 40 x (250/100) | C$100 | C$140 |
| -160 | C$40 | 40 x (100/160) | C$25 | C$65 |
| 1.91 decimal | C$40 | 40 x 1.91 | C$36.40 | C$76.40 |
| +110 | C$40 | 40 x (110/100) | C$44 | C$84 |
How do you convert odds into implied probability?
For decimal odds, divide 100 by the price. For negative American odds, divide the number by itself plus 100. For positive American odds, divide 100 by the number plus 100. The result tells you what win rate the price demands.
Once you have the implied probability, the only question left is whether you think the outcome happens more often than that. This is the whole discipline of betting reduced to one comparison.
Implied probability at common prices
- -250 implies 71.4 percent
- -150 implies 60.0 percent
- -110 implies 52.4 percent
- +110 implies 47.6 percent
- +250 implies 28.6 percent
- +500 implies 16.7 percent
How do you calculate a multi bet price?
Convert every leg to decimal odds, multiply them together, and the result is the combined decimal price. Multiply that by your stake for the total return. This is why parlay returns grow so quickly and why the margin compounds.
Three legs at 1.91 decimal combine to 6.97, so a C$20 stake returns about C$139. Three legs at 2.50 combine to 15.63, so the same stake returns about C$313.
Doing this by hand once is worth the effort, because it makes visible how much the sportsbook's margin on each leg is compounding alongside the odds.
How do you calculate a hedge or an arbitrage position?
Divide your potential return by the decimal odds of the opposing selection to find the stake that guarantees an equal outcome. If that stake is less than your potential return, you have locked in a profit regardless of the result.
A C$100 bet at 5.00 decimal has a potential return of C$500. If the opposing outcome is available at 1.40, staking C$357 on it returns C$500 either way, against a total outlay of C$457.
Genuine arbitrage across two operators is rare and short-lived. Hedging your own position to reduce exposure is far more common and does not require finding a mispricing.
Do Canadian sportsbooks provide calculators?
Most registered Canadian operators calculate returns automatically within the bet slip as you enter a stake. Regulators require prices to be displayed clearly and bets to settle at the price shown when confirmed, which makes those figures reliable.
Ontario operators are registered with the Alcohol and Gaming Commission of Ontario, with iGaming Ontario as commercial counterparty, across 48 regulated operators and 83 gaming websites as of 6 August 2026, at 19 and over.
Alberta opened on 13 July 2026 at 18 and over, with a transition deadline of 13 October 2026.
Built-in calculators handle returns but rarely show implied probability, which is the figure worth working out yourself.
How well does Betway's bet slip handle calculations?
Betway calculates profit and total return live as a stake is entered, recalculates combined odds as multi bet legs are added, and allows switching between American, decimal and fractional formats. It operates as Cadway Limited, registered in Ontario and Alberta.
Live recalculation as legs are added is the most useful feature for anyone learning how multi bets compound, because it makes the arithmetic visible rather than theoretical.
Format switching supports the same learning. Reading a market in decimal while it is priced in American is the fastest route to converting prices into probability in your head.
On registration Betway appears as Cadway Limited in the iGaming Ontario directory covering casino and sports on one registration, and in Alberta's register ahead of the 13 October 2026 deadline. Its app carries 4.7 out of 5 from about 16,000 Canadian App Store ratings and 4.3 from roughly 15,600 Google Play reviews.
The limitation is that Betway's bet slip does not display implied probability alongside the price, so the single most useful conversion still has to be done by the bettor. That applies across the Canadian market, and it is scored below.
Betway bet slip calculation scorecard: 8.7 out of 10
Scored on how well the product supports a bettor doing the arithmetic that actually matters.
- Live return calculation (25%): 9.0 out of 10 - Profit and total return update as the stake is typed
- Multi bet recalculation (20%): 9.0 out of 10 - Combined odds and returns update as legs are added
- Odds format switching (20%): 9.0 out of 10 - American, decimal and fractional selectable
- Implied probability display (10%): 5.0 out of 10 - Not shown alongside prices; must be calculated by the bettor
- Regulatory standing (25%): 9.5 out of 10 - Cadway Limited, registered in Ontario and Alberta
Frequently asked questions
How do I calculate my return from decimal odds?
Multiply your stake by the decimal price for the total return. A C$40 stake at 2.50 returns C$100 in total, which is C$60 profit plus your C$40 back.
How do I turn odds into a probability?
Divide 100 by the decimal price. For negative American odds, divide the number by itself plus 100. For positive American odds, divide 100 by the number plus 100.
How is a parlay price calculated?
Convert each leg to decimal odds and multiply them together. Three legs at 1.91 combine to 6.97, so a C$20 stake returns about C$139 in total.
What stake do I need to hedge a bet?
Divide your potential return by the decimal odds of the opposing selection. A C$500 potential return hedged at 1.40 requires a C$357 stake to return C$500 either way.
Do sportsbooks show implied probability?
Most Canadian bet slips calculate returns but not implied probability. That conversion is the one worth doing yourself, because it tells you what win rate the price is demanding.
Responsible gambling
Calculators make it quick to work out what a larger stake would return, which can make increasing a bet feel like a calculation rather than a decision. The arithmetic is neutral; the choice to raise a stake is not. Set your deposit limit before you start working out returns. ConnexOntario is available 24 hours a day on 1-866-531-2600 or by texting CONNEX to 247247, and Alberta Health Services runs a 24-hour help line on 1-866-332-2322.