Betting, explained like a person would.
Never placed a bet? Start here. Five minutes and every number on Spot Angle will make sense. Anywhere on the site, tap a dotted word or a ? for a quick definition.
The 3 bet types
1. The spread
Sportsbooks give the weaker team a head start so both sides are a fair bet.
Chiefs −7 vs Raiders +7. Bet the Chiefs and they must win by 8+. Bet the Raiders and they can lose by up to 6 and you still win.
Win by exactly 7? That's a push: you get your money back.
2. The total (over/under)
A guess at both teams' combined points. You pick over or under.
Total 44.5. Final 24–21 = 45 points: over wins. Final 20–17 = 37: under wins.
The .5 means it can't tie.
3. The moneyline
Just pick the winner. The price tells you the payout.
+150: bet $100, win $150 (underdog).
−150: bet $150 to win $100 (favorite).
How to read a Spot Angle result
Teams favored by a touchdown or more while playing away from home.
- Against the spread: 43.6% cover · 134–173–7
- These teams beat the spread 134 times and fell short 173 times (7 pushes). They win games but often not by enough.
- The angle: Fade them, 56.4%
- Betting the other team (the home underdog) won 56.4% of the time, above the 52.4% breakeven.
- +7.4u per 100 bets
- $100 on every one of those games would have made about $740 per 100 bets after the sportsbook's cut.
- “Could still be luck: treat as a lean”
- About 300 games is a decent sample but not proof. “Strong signal” would mean very unlikely to be chance.
History shows what happened, not what will happen. Markets adjust once a pattern becomes popular.
Prediction markets (Kalshi) in 2 minutes
Every contract pays $1 or $0
You buy “yes” on something happening, like Bears win. If it happens you get $1 per contract. If not, $0.
The price is the market's probability. Buying at 51¢ means the market gives the Bears about a 51% chance. Your profit if they win: 49¢, minus a small fee.
Where the edge comes from
You only make money long-term when the real chance is higher than the price.
Spot Angle compares Kalshi's price to how often teams at the same point spread have actually won (“line-implied”). A team at 51¢ that teams in its spot win 55% of the time is a price gap worth a look.
Baskets: buying several outcomes
Buy the top 3 Super Bowl favorites at 15¢ + 12¢ + 11¢ = 38¢. If any one wins, you get $1.
The catch: 38¢ also means the market thinks there's a 62% chance none of them win. It's only a good bet if you believe their real combined chance is higher than what you pay.
Watch out for long shots
Across sportsbooks and prediction markets, cheap long shots tend to win less often than their price suggests. People overpay for lottery tickets.
Spot Angle flags contracts under 10¢ for this reason.
Small edges that add up
- Shop for the best price
Different sportsbooks and Kalshi often price the same game differently. Our tools page compares them.
- Respect key numbers
About 1 in 7 NFL games ends with a 3-point margin. Getting +3.5 instead of +2.5 is worth more than almost any trend.
- Trust big samples
A trend over 500 games beats a hot streak over 10. Look for "Solid" or "Strong signal."
- Size bets small
Pros risk 1–2% of their bankroll per bet. Even a real 55% edge loses 10 bets in a row sometimes.
- Mind the fees
Every bet has a cost built in: −110 on sportsbooks, fees on Kalshi. An edge has to beat that first.
- Avoid long-shot baskets
Many cheap contracts feel safe together, but long shots are usually overpriced.
Glossary
- Point spread
- A head start in points that sportsbooks give the weaker team so both sides are a fair bet.
- Example: Chiefs −7 vs Raiders +7: a Chiefs bet only wins if they win by more than 7. A Raiders bet wins if they lose by fewer than 7 or win outright.
- Favorite (−)
- The team expected to win. Its spread has a minus sign, like −7.
- Underdog / dog (+)
- The team expected to lose. Its spread has a plus sign, like +7. "Dog" is short for underdog.
- Total (over/under)
- The sportsbook's guess for both teams' combined points. You bet whether the real score goes over or under it.
- Example: Total 44.5: a 24–21 final (45 points) is an over.
- Moneyline (ML)
- A bet on who wins the game, no points involved. The price shows how much you win or risk.
- Example: +150 means a $100 bet wins $150. −150 means you risk $150 to win $100.
- −110
- The standard price on spread and total bets: you risk $110 to win $100. That extra $10 is the sportsbook's cut. It's why you need to win more than half your bets just to break even.
- Vig (juice)
- The sportsbook's built-in fee. At −110 you must win 52.4% of bets to break even, not 50%.
- Push
- A tie with the spread or total. Your money is refunded.
- Example: Team −3 wins by exactly 3: push.
- Closing line
- The final spread or total right before kickoff. It's the market's most informed number, so all Spot Angle history uses it.
- Key numbers
- Margins NFL games land on most often, mainly 3 and 7 (field goals and touchdowns). Getting +3.5 instead of +2.5 matters far more than +5.5 vs +4.5, because so many games end exactly at 3.
- Half point (.5)
- Lines ending in .5 can't push. Shopping for an extra half point around 3 or 7 is one of the simplest edges.
- Bye / short week
- A bye is a week off (extra rest). A short week means playing again after only 4–5 days, like a Thursday game.
- Division game
- A game between two teams in the same division. They play twice a year and know each other well.
- Prime time
- Night games on national TV: Thursday, Sunday and Monday night.
- Dome
- An indoor stadium. Wind and cold don't affect the game.
- @ and vs
- @ means the team is playing away, at the other team's stadium. vs means the team is at home (or at a neutral site).
- Neutral site
- A game at a stadium that is neither team's home, like the international games in London or Germany. No home-field edge.
- Bankroll
- The total money you've set aside only for betting. Bet sizes are a small slice of it so a losing streak can't wipe you out.
- Kelly formula
- A classic rule for sizing bets: the bigger your edge, the bigger the bet. We use a cautious fraction of it and cap it at 5%.
- Decimal (European) odds
- Odds shown as the total you get back per $1, including your stake. 1.91 means a $100 bet returns $191 ($91 profit).
- Line movement
- Spreads and totals change during the week as money and news come in. Betting early, before the number shifts against you, locks in the better line.
- ATS (against the spread)
- Whether a team beat the point spread, not just the game.
- Example: A team at −7 that wins by 10 covered ATS. Win by 4 and they won the game but lost ATS.
- Cover
- To beat the spread. Cover rate = how often a group of teams beat the spread.
- Straight up (SU)
- Who actually won the game, ignoring the spread.
- Record (W–L–P)
- Wins, losses and pushes for the bet in question.
- Example: 120–100–5 = 120 wins, 100 losses, 5 refunds.
- Units
- Profit counted in bet sizes. +10u means you'd be up 10 bets' worth. If your bet is $100, that's +$1,000.
- ROI
- Return on investment: average profit per bet as a percent of what you risked.
- Fade
- Bet against a team or situation, on the assumption that it's overrated.
- Signal vs noise
- Our check on whether a record is likely real or just luck, based on how many games it covers and how far it is from 50%. A 7–3 run means nothing; 700–300 almost certainly means something. "Likely noise" means don't trust it yet.
- Breakeven
- The win rate you need to not lose money. At −110 it's 52.4%.
- Line
- The point spread for that team in that game. −3.5 means they were favored by 3.5 points. +3.5 means they were a 3.5-point underdog.
- Example: PK (pick'em) means a spread of 0: no favorite, so whoever wins covers.
- Cover margin
- How many points teams beat (+) or missed (−) the spread by, on average. +2.0 means they beat the line by 2 points a game.
- ATS result (W / L / P)
- W = the team beat the spread. L = it didn't. P = push: it landed exactly on the spread and bets were refunded.
- Over/under result (O / U / P)
- O = the two teams' combined score went over the total. U = under. P = landed exactly on it (refund).
- Likely noise / Lean / Solid / Strong
- How much to trust a record. "Likely noise" means it could easily be luck. Lean, Solid and Strong mean it's increasingly unlikely to be luck. We check how far the record is from 50% and how many games it covers. 7–3 is noise; 700–300 is strong.
- Edge
- How much better your chance of winning is than what the price implies. No edge means the bet loses money over time.
- Kalshi
- A US-regulated exchange where you buy yes/no contracts on events, including sports, that pay $1 if they happen.
- Contract
- One share of an outcome. It pays $1 if it happens and $0 if it doesn't.
- Example: Buy "Chiefs win" at 62¢. If they win you get $1 (38¢ profit). If not, you lose your 62¢.
- Price = probability
- A contract's price in cents is roughly the market's chance it happens. 25¢ ≈ 25%.
- Ask / bid
- Ask is the cheapest price you can buy at right now. Bid is the most someone will pay to buy it from you.
- Basket
- Buying several outcomes in the same market so you win if any one of them hits.
- Expected value (EV)
- What a bet makes or loses on average if you made it many times. Positive EV = profitable long term.
- Kalshi fees
- Kalshi charges a small fee per trade, highest for contracts near 50¢. We include it in every calculation.
- House cut (overround)
- How much all outcomes' prices add up to above 100%. That extra is the built-in cost of trading the market.
- Arbitrage (locked profit)
- When buying every outcome costs less than the $1 payout after fees, you profit no matter what. Rare and short-lived.
- Long-shot bias
- Cheap long shots tend to win less often than their price suggests, in both sportsbooks and prediction markets. Be skeptical of contracts under about 10¢.
- Popular spots
- Ready-made situations bettors often research. Tap one to load it, then change any filter you like.
- Example: "Double-digit dogs" = underdogs getting 10 or more points.
- Your win %
- Your own estimate of how likely the outcome is. We compare it to the price to tell you if the bet is worth it. If you're unsure, leave it blank.
- Spot / angle
- A betting situation, like "home underdogs off a bye." Spot Angle shows how that situation has done historically.
- Line-implied win %
- How often teams with this exact point spread have actually won, from 20+ years of games. It translates the sportsbook line into a probability.
- Price gap
- When Kalshi's price differs from the line-implied win %. A team at 51¢ that teams with its spread win 55% of the time may be cheap.
Spot Angle is a research tool, not betting advice. Only bet what you can afford to lose. 21+. Problem gambling help: 1-800-GAMBLER.