Betting odds: the three formats, side by side

One number, three costumes

American odds pivot around a hundred. A minus number is what you risk to win a hundred; a plus number is what a hundred wins you. Favourites get the minus.

Decimal odds fold the stake into the return. 2.50 means ten dollars comes back as twenty five, not twenty five profit. This is the format almost every Canadian app defaults to and the one we use throughout this site.

Fractional odds are the profit-to-stake ratio. 3/1 pays three for every one risked, which is decimal 4.00 and American +300.

The conversion table you actually need

Even money: 1/1, 2.00, +100, implied 50%.

Short favourite: 1/2, 1.50, −200, implied 66.7%.

Standard line: 10/11, 1.91, −110, implied 52.4%.

Modest underdog: 6/4, 2.50, +150, implied 40%.

Long shot: 9/1, 10.00, +900, implied 10%.

The implied column is the useful one. Anything you can turn into a percentage you can compare against your own opinion, and that comparison is the only judgement a bettor actually makes.

Doing the conversion in your head

Decimal to percentage: one divided by the price. 4.00 gives 25%.

American minus to percentage: the number over itself plus a hundred. −180 gives 180 ÷ 280, so 64.3%.

American plus to percentage: a hundred over the number plus a hundred. +240 gives 100 ÷ 340, so 29.4%.

Nobody does the third one at speed. Set the app to decimal and the whole problem disappears.

Why both sides add to more than a hundred

Take a two-way market priced 1.91 each side. Both convert to 52.4%, which totals 104.8%. Those extra four and a bit points are the book's margin and they are charged whichever team wins.

The size of that margin varies enormously. Headline markets at the sharper books sit down near 4%. Prop markets and long parlays run several times wider, which is exactly why the app's front screen is full of them.

Adding up a market takes fifteen seconds and it tells you more about a sportsbook than any review, including this one.

On the handset

Set the odds format once, in settings, and never touch it. Mixed formats across two apps is how a stake ends up in the wrong box.

Set odds-change acceptance to ask rather than accept. Prices move while your thumb is travelling, and the difference between the number you saw and the number you got is real money you never agreed to spend.

Then compare. Two apps open side by side, same market, eight seconds. It is the only edge available to somebody doing this for fun, and it is a genuine one.