Moneyline Calculator

You see −150 next to your team and +130 next to the underdog. You know one means “favorite” and the other means “long shot” — but how much do you actually win on a $100 bet at each? And what do those numbers secretly say about each team’s chances? The Moneyline Calculator at the top of this page decodes American odds instantly: enter the moneyline and your wager, and it shows whether you are betting a favorite or underdog, your potential profit, the total payout, and the implied probability — each as its own labeled row in the result box.

This guide explains how moneyline odds work, the formulas for favorites and underdogs, what implied probability reveals about the sportsbook’s margin, two fully worked examples, and how smart bettors use these numbers. By the end, you will read any moneyline like a price tag.

How American Moneyline Odds Work

American odds center on the number 100 — think of it as the reference wager. A negative number like −150 marks the favorite: it tells you how much you must bet to win $100 in profit. At −150, you risk $150 to win $100. A positive number like +130 marks the underdog: it tells you how much profit a $100 bet wins. At +130, a $100 wager profits $130.

The sign is the whole story: minus means “risk more than you win” (the outcome is likely, so the payout is short), plus means “win more than you risk” (the outcome is unlikely, so the payout is generous). The bigger the absolute number, the stronger the signal — −800 is a near-certainty priced accordingly, +800 a moonshot.

Unlike point spreads, a moneyline bet has no margin to cover: your team simply has to win the game outright. That simplicity is why moneylines dominate baseball and hockey (low-scoring sports where one run decides everything) and appear for every football and basketball game too.

The Formulas: Profit, Payout, Probability

For an underdog (+odds): profit = wager × odds ÷ 100. A $100 bet at +130 profits $130. The total payout — what the sportsbook hands you back, stake included — is wager + profit, so $230 here.

For a favorite (−odds): profit = wager × 100 ÷ |odds|. A $100 bet at −150 profits $66.67, for a total payout of $166.67. Notice the symmetry: at −150 you need to risk $150 to profit $100, exactly the definition.

Implied probability converts the odds into the win chance the price assumes. For positive odds: 100 ÷ (odds + 100) — so +130 implies 100/230 ≈ 43.48%. For negative odds: |odds| ÷ (|odds| + 100) — so −150 implies 150/250 = 60%. This is the single most useful number in betting: it tells you what the market believes, letting you compare against your own assessment.

The Vig: Why Implied Probabilities Sum Past 100%

Add the implied probabilities of both sides of a typical game — say −150 (60%) and +130 (43.48%) — and you get 103.48%, not 100%. That extra 3.48 percent is the vig (vigorish), the sportsbook’s built-in margin. It is how books profit regardless of outcome: they take slightly more in total implied probability than exists in reality.

The vig is the reason “picking winners” is not enough to profit long-term. If you bet both sides of every game at those prices, you lose 3.48 percent per cycle on average. To beat the vig, your picks must be right more often than the implied probabilities suggest — you need edges, wagers where your estimated probability exceeds the implied one. The calculator’s implied-probability row is therefore not trivia; it is the hurdle rate every bet must clear.

Vig varies by market: major NFL sides might carry 4–5 percent, while obscure props can exceed 10 percent. Shopping lines across books — one offering −145 where another offers −155 — is the simplest legal edge available, and the calculator makes the comparison instant.

How to Use the Moneyline Calculator

1. Enter the moneyline odds — negative for favorites (e.g. −150), positive for underdogs (e.g. 130). Type 130 for +130.
2. Enter your wager amount in dollars — the dollar sign sits outside the input; just type the number.
3. Press Calculate. Four labeled rows appear: Bet Type (Favorite or Underdog, with the odds), Potential Profit, Total Payout (stake + profit), and Implied Probability as a percentage.
4. Press Reset to price another bet or compare lines between sportsbooks.

Worked Example: Betting the Favorite at −150

You like the home favorite at −150 and wager $100:

1. Bet type: Negative odds → Favorite (−150), shown in the Bet Type row.
2. Potential profit: $100 × 100 ÷ 150 = $66.67, the Potential Profit row.
3. Total payout: $100 + $66.67 = $166.67, the Total Payout row — what you collect on a win.
4. Implied probability: 150 ÷ (150 + 100) = 60.00%, the Implied Probability row.

The market says this team wins 3 times in 5. Your $100 risks a full $100 to make $66.67 — the classic favorite’s bargain: high win rate, thin reward. You should only take it if you believe the true win chance exceeds 60 percent.

Worked Example: Betting the Underdog at +130

You fancy the road underdog at +130, same $100 wager:

1. Bet type: Positive odds → Underdog (+130), the Bet Type row.
2. Potential profit: $100 × 130 ÷ 100 = $130.00, the Potential Profit row.
3. Total payout: $100 + $130 = $230.00, the Total Payout row.
4. Implied probability: 100 ÷ (130 + 100) ≈ 43.48%, the Implied Probability row.

The market gives this team about a 4-in-9 shot, but pays $130 profit on $100 risk. Underdog betting is a lower-hit-rate, higher-reward game: you can lose more bets than you win and still profit, provided your winners arrive more often than 43.48 percent of the time.

Converting Between Odds Formats

The world uses three odds dialects, and fluency helps. Decimal odds (European standard) express total payout per unit staked: −150 converts to 1.67 (a $100 bet returns $166.67), +130 to 2.30. The conversion: for negative American odds, decimal = 1 + 100/|odds|; for positive, decimal = 1 + odds/100.

Fractional odds (UK standard) express profit relative to stake: −150 is 2/3 (profit $2 for every $3 staked), +130 is 13/10. American odds translate directly: +130 means 130/100, reducible to 13/10; −150 means 100/150, or 2/3.

Implied probability is the universal translator underneath all three — 60 percent is 60 percent in every format. When a European site shows 1.67 and your book shows −150, the calculator’s probability row confirms they are the same price, letting you spot which book is actually offering value.

Moneyline vs. Point Spread: When Each Makes Sense

Every game offers both a moneyline and a point spread, and choosing between them is a pricing decision, not a loyalty test. The point spread handicaps the favorite — say, −7 points — so both sides pay roughly −110; you win by picking the winner against the spread. The moneyline skips the handicap: pick the outright winner, with the odds doing all the adjusting.

As a rule of thumb, big favorites are often cheaper on the spread, big underdogs on the moneyline. Laying −400 on a heavy football favorite risks $400 to win $100; taking −7 at −110 risks $110 for the same $100 with a much better payout ratio — if you trust the blowout. Conversely, a +300 underdog’s moneyline pays triple the spread’s even money, which compensates for the lower hit rate. Professionals routinely split the difference: moneyline on underdogs they genuinely like, spread on favorites they expect to dominate.

In low-scoring sports like baseball and hockey, the moneyline is the main market — run lines and puck lines (the −1.5 spread equivalents) exist but handle less volume and often carry worse pricing. The calculator prices the moneyline leg of any of these decisions; run the underdog moneyline and the favorite spread through it, compare implied probabilities against your own, and take whichever side the numbers favor.

Using Implied Probability to Find Value

Value betting is the entire professional game in one sentence: bet only when your estimated probability exceeds the implied probability. If the calculator says −150 implies 60% and your research — models, injuries, matchups — says the team wins 66 percent of the time, you have a 6-point edge. Repeated over hundreds of bets, edges compound into profit; without them, the vig grinds you down.

This discipline also cures the most expensive amateur habit: betting favorites because “they’ll probably win.” Probably winning is already priced in — that is what −150 means. The question is never “will they win?” but “will they win more often than the price demands?” A +200 underdog you rate at 40 percent (versus 33.33 percent implied) is a better bet than a −200 favorite you rate at 68 percent (versus 66.67 percent implied), even though the favorite wins far more often.

Bankroll management completes the system: professionals risk 1–2 percent of bankroll per bet (the Kelly criterion formalizes the optimal fraction from your edge). A $1,000 bankroll means $10–$20 wagers — boring, but it survives the inevitable losing streaks that destroy undisciplined bettors. The calculator prices the bet; discipline prices your survival.

Live Betting: Moneylines in Motion

Modern sportsbooks price moneylines in-game, updating odds after every score, drive, or inning. A pregame −150 favorite that falls behind early might drift to +110 as an underdog — and this is where the calculator earns its keep a second time. Each live price carries a fresh implied probability, and comparing it against the actual game state is the essence of live value betting.

The trap of live betting is emotional: falling behind feels like the game is lost, but the market usually overreacts to early events, especially in long games like baseball or basketball where comebacks are common. If your pregame analysis said a team wins 62 percent of the time and they are now priced at +110 (implying 47.6 percent) after one bad quarter, the market has likely handed you an edge — provided nothing structural (like an injury) caused the swing. Run every live price through the calculator, compare against your read of the game, and let the implied probability — not the scoreboard panic — decide.

Tips for Smarter Moneyline Betting

1. Always check the implied probability first. It is the price tag — never bet without reading it.
2. Bet numbers, not teams. Loyalty to a team is the fastest way to pay full vig on bad prices.
3. Shop lines across sportsbooks. −145 versus −155 on the same game is free money left on the table.
4. Demand an edge over implied probability before placing any wager — your estimate must beat the market’s.
5. Risk 1–2 percent of bankroll per bet. Survival beats excitement; losing streaks are mathematically certain.
6. Track every bet with its closing line. Beating the closing line consistently proves your process works, even during downswings.
7. Favorites need high hit rates; at −150 you must win 60% just to break even — respect the math.
8. Underdogs forgive losses; at +130 you profit winning just 44% — but variance is brutal, so size down.
9. Ignore “lock” talk. There are no locks, only probabilities; anyone selling certainty is selling something else.
10. Set a stop-loss and a time budget. Decide your maximum weekly loss before the week starts, and walk away when you hit it.

Frequently Asked Questions

1. What does −150 mean in betting?

It marks the favorite: you must wager $150 to profit $100. A $100 bet at −150 profits $66.67 and implies a 60% win probability.

2. What does +130 mean in betting?

It marks the underdog: a $100 wager profits $130. The total payout is $230 and the implied win probability is about 43.48%.

3. How does this calculator compute my potential profit?

For positive odds: wager × odds ÷ 100. For negative odds: wager × 100 ÷ |odds|. Total payout adds your original stake back.

4. What is implied probability?

The win chance the odds price in: 100/(odds+100) for underdogs, |odds|/(|odds|+100) for favorites. It is the hurdle your own estimate must beat for a bet to have value.

5. Why do the two sides’ probabilities add up to more than 100%?

The excess is the vig — the sportsbook’s margin, typically 3–5% on major markets. It is why you must beat the implied probabilities, not just pick winners, to profit.

6. What is the difference between profit and payout?

Profit is what you win beyond your stake; payout (or “return”) is profit plus your original wager back. A $100 bet at +130 has $130 profit and $230 payout.

7. How do I convert American odds to decimal odds?

For negative odds: 1 + 100/|odds| (−150 → 1.67). For positive: 1 + odds/100 (+130 → 2.30). Decimal odds show total return per unit staked.

8. Is it better to bet favorites or underdogs?

Neither inherently — value decides. Favorites win more often but pay thinly; underdogs lose more often but pay generously. Bet whichever side your probability estimate says is mispriced.

9. What does “bet type” mean in the results?

It simply labels your wager as Favorite (negative odds) or Underdog (positive odds) and echoes the odds, so the price context is always visible.

10. Can I use this for parlays?

Not directly — parlay math multiplies the decimal odds of each leg. Price each leg here first, convert to decimal, multiply them, and you have the parlay price.

11. What is line shopping?

Comparing the same bet across sportsbooks to take the best price — e.g. −145 instead of −155. It is the simplest legitimate edge in betting.

12. How much should I wager per bet?

Professionals risk 1–2% of bankroll per bet. This survives inevitable losing streaks that wipe out bettors who stake emotionally.

13. What is the Kelly criterion?

A formula for optimal bet sizing from your edge: bet fraction = (probability × decimal odds − 1) ÷ (decimal odds − 1). Most pros use a fraction of full Kelly to tame volatility.

14. Do moneyline odds change before the game?

Constantly — with betting action, injury news, and weather. The odds you bet at are locked in; later moves do not affect settled wagers.

15. Is sports betting a reliable way to make money?

No. The vig ensures most bettors lose long-term; only disciplined, edge-based betting with strict bankroll management has any chance, and even professionals endure long downswings.

CONCLUSION

A moneyline is a price tag written in a code — minus for favorites, plus for underdogs, both pivoting around 100. The Moneyline Calculator decodes it into the four numbers that matter: your bet type, your profit, your total payout, and the implied probability the market is charging. Read the probability first, demand an edge over it, size your wagers to survive, and never confuse “likely to win” with “good value.” The sportsbook’s margin is built into every price; the bettor’s only weapon is sharper arithmetic.