Free tool
Odds converter and overround calculator
Type a price in any format to see it in every other one, then add up a whole market to see the bookmaker's margin. For readers 21 and over.
Convert odds
- Decimal
- 1.91
- American (moneyline)
- -110
- Hong Kong
- 0.91
- Malay
- 0.91
- Indonesian
- -1.10
- Implied probability (%)
- 52.36%
A ₱100 stake at these odds returns ₱191 if it wins (₱91 profit plus the stake). To break even over time, bets at this price must win more than 52.4% of the time.
Rounded for display. Sportsbooks round prices too, so a converted figure can differ from the screen by a cent or a point.
Overround and margin
Overround (book total)
104.71%
Margin
4.71%
Under the proportional split, a ₱100 bet on any outcome returns about ₱95.50 on average.
| Outcome | Decimal | Implied (1 ÷ price) | Fair, proportional | Fair price |
|---|---|---|---|---|
| 1 | 1.91 | 52.36% | 50.00% | 2.00 |
| 2 | 1.91 | 52.36% | 50.00% | 2.00 |
| Total | 104.71% | 100.00% |
"Fair" here divides each implied probability by the total, which spreads the margin in proportion to each price. A bookmaker need not spread it that way, and the prices alone cannot show how it did. Enter every outcome of the market, or the total means nothing.
How the conversion works
Every format describes the same thing: what a winning bet pays. The calculator turns what you type into a decimal price D (total return per 1 staked, stake included) and writes D in each format. The prices below are invented examples, not anyone's current odds.
| Format | From decimal D | Back to decimal |
|---|---|---|
| American | D ≥ 2: +(D − 1) × 100. D < 2: −100 ÷ (D − 1) | +A: 1 + A ÷ 100. −A: 1 + 100 ÷ A |
| Hong Kong | D − 1 | HK + 1 |
| Malay | D ≤ 2: D − 1. D > 2: −1 ÷ (D − 1) | Positive M: 1 + M. Negative M: 1 + 1 ÷ |M| |
| Indonesian | D ≥ 2: D − 1. D < 2: −1 ÷ (D − 1) | Positive I: 1 + I. Negative I: 1 + 1 ÷ |I| |
| Implied probability | 100% ÷ D | 100 ÷ P |
Three worked conversions
- American −150 (a favourite): D = 1 + 100 ÷ 150 = 1.667. Hong Kong 0.667, Malay 0.667, Indonesian −1.50, implied 1 ÷ 1.667 = 60.0%.
- American +130 (an underdog): D = 1 + 130 ÷ 100 = 2.30. Hong Kong 1.30. Malay −1 ÷ 1.30 = −0.769, because Malay turns negative above HK 1.00. Indonesian +1.30, implied 43.5%.
- Decimal 1.91 (the usual price on each side of a spread or total): American −100 ÷ 0.91 = −109.9, shown as −110. Hong Kong and Malay 0.91, Indonesian −1 ÷ 0.91 = −1.10, implied 52.4%.
Negative Malay and Indonesian figures work like American minus prices: Indonesian −1.10 means stake 1.10 to win 1, the same as American −110 stakes 110 to win 100. Hong Kong, Malay and Indonesian figures quote profit only; decimal includes the stake, which is why decimal is always the HK figure plus 1.
How the margin works
- Turn each outcome's price into an implied probability: 1 ÷ decimal price.
- Add them. That total is the overround. A market with no margin would add to exactly 100%.
- Margin = overround − 100%.
Invented two-way moneyline: Team A 1.80, Team B 2.00. Team A implies 1 ÷ 1.80 = 55.56%, Team B 1 ÷ 2.00 = 50.00%, total 105.56%, so the margin is 5.56%.
Removing the margin (proportional method). The calculator's "fair" column divides each implied probability by the total: 55.56 ÷ 1.0556 = 52.63% for A and 50.00 ÷ 1.0556 = 47.37% for B, which add to 100%. The fair prices are 1 ÷ 0.5263 = 1.90 and 1 ÷ 0.4737 = 2.11. A different method, the additive one, takes an equal slice off each side instead (5.56 ÷ 2 = 2.78 points each), giving 52.78% and 47.22%. The two methods disagree more as prices drift apart and the field grows, and neither tells you how a particular bookmaker built its prices. Treat the fair column as an estimate.
Under the proportional split, the average return of a ₱100 bet is ₱100 ÷ 1.0556 = about ₱94.74 on either team. Backing the favourite or the underdog does not change that; the market sets it.
Reading the numbers
- Enter every outcome. A total from half a market is meaningless. Basketball moneylines have two outcomes; a conference-winner market has one per team still in it.
- Bigger fields, bigger margins. The PBA guide works through an invented four-team conference market that adds to 115.6%, about three times a typical single game. The NBA guide shows how three parlay legs at 1.91 compound the margin.
- Break-even rate. The implied probability is the share of bets at that price you must win just to stay level. At 1.91 that is 52.4%, not 50%.
- A low margin is not a reason to bet. It only lowers the average cost. You still lose over time.
Markets and the moneyline, spread and total explained from the start: how to read basketball odds. All basketball guides: PBA and NBA hub. Before you open an account, check the site's exact address with the licence checker, and read whether PBA and NBA betting is legal for you.
Betting is for adults 21 and over and is a risk of loss, not a way to earn. Set a limit before you start and never chase losses. If it stops being fun, see responsible gambling or call the PAGCOR helpline, 02-8248-9568.
Frequently asked questions
How do I convert American odds to decimal?
For a plus price, divide by 100 and add 1: +130 → 1 + 1.30 = 2.30. For a minus price, divide 100 by the number without its sign and add 1: -150 → 1 + 100 ÷ 150 = 1.67.
What is the difference between Hong Kong and Malay odds?
Hong Kong odds are the profit per 1 staked, so they are always positive (decimal minus 1). Malay odds match Hong Kong up to 1.00; above that they turn negative, written as -1 divided by the Hong Kong figure. HK 1.30 is Malay -0.77.
What is overround?
The total of the implied probabilities of every outcome in a market. A fair market adds to 100%; the amount above 100% is the bookmaker's margin. Two sides at 1.91 add to about 104.7%, a margin of about 4.7%.
Paano malalaman ang margin ng bookmaker?
Hatiin ang 1 sa bawat decimal odds, pagkatapos pagsamahin. Kapag lumampas sa 100%, ang sobra ang margin. Halimbawa (gawa-gawa): 1.80 at 2.00 → 55.6% + 50% = 105.6%, kaya 5.6% ang margin.
Can a lower margin make betting profitable?
No. A smaller margin only means you lose less on average. Over many bets the margin still works against you, whichever outcome you back.
Is anything I type sent to you?
No. The arithmetic runs in your browser and nothing is stored or sent.