If you can't read odds quickly, you can't spot value. And if you can't spot value, you're a tourist - paying the bookie's margin every time you click. This guide takes you from "what does 2.10 even mean?" to "I can convert any odds format into a probability and back" in nine minutes.
SA bookies - Hollywoodbets, YesPlay, Betway, Supabets - default to decimal odds. International sharp shops sometimes use fractional (UK style) or American. You should be able to read all three.
| Format | Example | What it means |
|---|---|---|
| Decimal | 2.10 | R100 stake returns R210 (R100 stake + R110 profit) |
| Fractional | 11/10 | Bet 10, win 11 in profit (plus your stake back) |
| American | +110 | R100 stake wins R110 (positive = underdog) |
All three describe the same payout. They just look different.
The default in South Africa. Multiply your stake by the decimal to get total return.
That's it. Total return = stake × odds. Profit = total return - stake.
The bookie isn't telling you "this team has a 47% chance to win" out loud. They're telling you in odds. You convert. The formula:
Implied probability (%) = 100 ÷ decimal odds
Examples:
Now you can compare what the bookie thinks against what you think. That's the entire game.
Add up the implied probabilities of every outcome in a match. If they total 100%, the market is fair. They never do. They total 105-108%. That extra 5-8% is the bookie's margin - the "vig" or "juice".
Example PSL match:
| Outcome | Odds | Implied % |
|---|---|---|
| Sundowns win | 1.85 | 54.1% |
| Draw | 3.40 | 29.4% |
| Pirates win | 4.20 | 23.8% |
| Total | 107.3% | |
The bookie's margin is 7.3%. To find true probabilities, divide each implied % by the total:
That's a "no-vig" line. If your model says Pirates win 27% of the time, and the no-vig says 22%, you've got value. Bet it.
The shortcut every sharp bettor uses: compare your bookie's odds to Pinnacle (a sharp international bookie that runs on tiny margins, around 2.5%). Pinnacle's price is the closest thing to a "true" market price you can find publicly.
If YesPlay offers Sundowns at 2.10 and Pinnacle's no-vig price is 1.95 - you're getting 7.5% better than fair. Long-term, that's a winning bet.
Written like 5/2 or 11/4. The first number is profit, the second is stake. So 5/2 = bet 2 to win 5 (plus your stake back).
Convert to decimal: (top ÷ bottom) + 1
Two flavours: positive (underdog) and negative (favourite).
| Decimal | Implied % | Stake R100 → return |
|---|---|---|
| 1.20 | 83.3% | R120 |
| 1.50 | 66.7% | R150 |
| 1.80 | 55.6% | R180 |
| 2.00 | 50.0% | R200 |
| 2.50 | 40.0% | R250 |
| 3.00 | 33.3% | R300 |
| 4.00 | 25.0% | R400 |
| 5.00 | 20.0% | R500 |
Memorise the top half. The bottom half you can calculate in your head once you know the formula.
Because they can't tell you what the true probability is - that would expose the vig. Showing you decimal odds lets them embed margin invisibly.
Higher odds = lower probability. They pay more if they win, but they win less often. The question is always "are these odds higher than the true probability suggests?". That's value.
Pinnacle.com (or via odds-comparison sites like OddsPortal). It's not licensed in SA, but the price is freely visible and useful as a benchmark.