A unit in betting is the standard size of one bet, set as a fixed share of your bankroll, such as 1% to 5%. If your bankroll is $2,000 and your unit is 1%, one unit is $20, and a “2-unit play” means a $40 bet.
Units let bettors compare results without saying how much money they bet. A bettor who is “up 10 units” with $20 units has made $200; the same 10 units with $100 units is $1,000, and the record is the same either way.
How to set your unit size
Start with the bankroll: money set aside for betting only, money you can lose without it changing your rent, bills or savings. Then pick the share. Here is how a made-up $2,000 bankroll splits:
| Unit size | One unit | Units in the bankroll |
|---|---|---|
| 1% | $20 | 100 |
| 2% | $40 | 50 |
| 5% | $100 | 20 |
A smaller unit survives longer. At 1%, it takes 100 straight one-unit losses to empty the account. At 5%, it takes 20.
Keep the unit fixed for a set period, such as a month or a season, then recalculate from the new bankroll. If $2,000 falls to $1,600, a 1% unit falls from $20 to $16. That is the point: the bet size shrinks when the bankroll does.
Risking a unit or winning a unit
Units get confusing with prices below even money. The Los Angeles Chargers at Buffalo Bills on Sunday, September 27, 2026, had Buffalo -7 at -115 and the Chargers +7 at -105 at DraftKings, as listed on ESPN on the morning of September 24.
With a $20 unit, you can size a bet two ways:
- Risk one unit: $20 at -115 wins $17.39. $20 at -105 wins $19.05.
- To win one unit: you risk $23 at -115 to win $20, and $21 at -105 to win $20.
Pick one convention and stick to it. Risking one unit on favorites and betting to win one unit on underdogs means no single bet ever risks more than one unit. Whatever you choose, record it, because “+5 units” means different money under each.
Tracking a record in units
A record in units shows whether you are actually ahead. Say you bet one unit, to win, on 20 games at -110 and go 11-9. The 11 wins pay 11 units. The 9 losses cost 9 x 1.1 units, which is 9.9. You are up 1.1 units, or $22 with a $20 unit.
The price decides how often you need to win. At -110, you need to win 52.38% of the time to break even (110 divided by 210). At -115, it is 53.49%. A bettor who hits 52% at -110 is losing money slowly, and the unit record shows it where a win-loss record does not.
Why flat units beat chasing losses
Losing runs are normal, even for a bettor who wins more than they lose. A bettor who wins 55% of bets, over 200 bets, has about a 60% chance of at least one run of six straight losses somewhere in those 200, and about a 33% chance of seven in a row. That is simple probability, not a record of anyone’s betting.
With a 1% unit, six losses in a row costs 6% of the bankroll. With a 5% unit, it costs 30%. The bettor with the bigger unit is not wrong more often. They just run out of money sooner.
Doubling the next bet after a loss to “get it back” breaks the whole system. Six straight losses starting from one unit, doubling each time, costs 1 + 2 + 4 + 8 + 16 + 32 = 63 units, which is more than half of a 100-unit bankroll.
Changing the size of a bet
Betting 1, 2 or 3 units by how strongly you rate a bet only works if the ratings are tested: track the 1-unit, 2-unit and 3-unit bets separately, and if the 3-unit bets do not do better, stop sizing up.
A more formal method is the Kelly criterion, which sets each stake from your own estimate of the chance of winning and the price. The stake is (b x p – q) / b, where b is the profit per $1, p your chance of winning and q the chance of losing. At +100, where b is 1, a bettor who rates a bet at 55% gets (0.55 – 0.45) / 1, or 10% of the bankroll.
That figure is only as good as the 55%. If the real chance is 52%, the formula says 4%, so a small error in the estimate more than doubles the stake. Betting half of the Kelly figure is one way to allow for that: at 55%, that is 5%.
When a pick service quotes units
When a handicapper reports a record in units, ask two questions before trusting the number: what price the units were counted at, and whether each pick risked one unit or aimed to win one. For the services themselves, see our handicapper site reviews.
For somewhere to bet, see our sportsbook reviews, and for this week’s games and prices, our NFL predictions. If betting has stopped being a hobby you control, our page on responsible gambling is a place to start.