Teaser Calculator: When Buying Points Actually Has +EV

What a Teaser Is and Why the Math Is Different

A teaser lets you buy points on two or more spread or total selections in exchange for reduced odds. You move the line in your favor on every leg, but you pay for it with a worse payout. The question is not whether teasers feel safer. It is whether the extra win probability you buy is worth the price you pay.

Standard parlays multiply odds across independent legs. Teasers multiply adjusted probabilities across legs that have been shifted by a fixed number of points. The math is fundamentally different because the value of those bought points varies enormously depending on which numbers you cross.

A 6-point NFL teaser that crosses through 3 and 7 is a completely different bet than a 6-point teaser that moves a line from -8 to -2. Same structure, same price, wildly different expected value. The parlay calculator handles standard parlays. Teaser math requires understanding which key numbers create value.

The 3 Formulas Behind Teaser Math

Teaser valuation comes down to three calculations: the adjusted win probability for each leg, the combined probability of the teaser hitting, and the EV comparison against the price you pay.

Formula 1: Adjusted leg probability

Start with the de-vigged probability of each selection at the original line. Use the de-vig calculator to strip the sportsbook margin. Then estimate the probability gain from the bought points.

For NFL spreads, historical data gives approximate probability boosts per key number crossed:

A selection at -7.5 with a de-vigged probability of 48% that gets teased 6 points to -1.5 crosses through 7, 6, 4, and 3. The probability gain is roughly 5 + 2 + 2 + 9 = 18 percentage points. Adjusted probability: approximately 66%.

This is an approximation. The actual gain depends on the sport, the specific matchup, and how the margin of victory distributes around those numbers. NFL data is the most reliable because the sample size is largest and scoring clusters around 3 and 7.

Formula 2: Combined teaser probability

Multiply the adjusted probabilities of each leg:

Teaser hit rate = Leg 1 adjusted prob x Leg 2 adjusted prob x ... x Leg N adjusted prob

For a 2-leg teaser with adjusted probabilities of 66% and 71%:

Combined probability = 0.66 x 0.71 = 46.9%

Formula 3: Expected value

Compare the combined probability against the payout:

EV = (hit rate x net profit) - (miss rate x stake)

A standard 2-leg, 6-point NFL teaser pays -110 (bet $110 to win $100). With a 46.9% combined hit rate:

EV = (0.469 x $100) - (0.531 x $110) = $46.90 - $58.41 = -$11.51 per $110 bet

That is -10.5% EV. This teaser is a losing bet despite both legs having elevated individual win rates. The price is too high relative to the probability gained.

Now change the legs to selections that cross through both 3 and 7. Adjusted probabilities rise to approximately 72% and 74%:

Combined probability = 0.72 x 0.74 = 53.3%

EV = (0.533 x $100) - (0.467 x $110) = $53.30 - $51.37 = +$1.93 per $110 bet

That is +1.8% EV. Same teaser structure, same price. The difference is entirely in which key numbers the legs cross. Run any combination through the EV calculator to see where the line falls.

The 3/7 Rule: Where Teaser Value Lives

The single most important concept in teaser betting: NFL teasers have positive expected value almost exclusively when both legs cross through 3 and 7. This is the 3/7 rule.

Why these numbers? NFL games disproportionately end with margins of 3 (field goal) and 7 (touchdown). Roughly 15% of NFL games land on a margin of exactly 3. Another 9% land on exactly 7. Moving your line across these numbers captures the largest probability jumps per point bought.

Which original lines cross 3 and 7 with a 6-point tease?

For favorites (teasing down):

• -7.5 to -1.5: crosses 7, 6, 5, 4, 3, 2. Hits both key numbers.
• -8 to -2: crosses 7, 6, 5, 4, 3. Hits both key numbers.
• -8.5 to -2.5: crosses 8, 7, 6, 5, 4, 3. Hits both.
• -9 to -3: crosses 8, 7, 6, 5, 4. Hits 7 but lands ON 3 (push at 3 if not half-point). Less valuable.

For underdogs (teasing up):

• +1.5 to +7.5: crosses 2, 3, 4, 5, 6, 7. Hits both.
• +1 to +7: crosses 2, 3, 4, 5, 6. Hits 3, lands ON 7 (push risk).
• +2 to +8: crosses 3, 4, 5, 6, 7. Hits both.
• +2.5 to +8.5: crosses 3, 4, 5, 6, 7, 8. Hits both.

The sweet spots for 6-point teasers are original lines between -8.5 and -7.5 for favorites, and between +1.5 and +2.5 for underdogs. Outside these ranges, you are paying for points that do not cross enough key numbers.

Step 1Find selections with lines near 3 and 7

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Step 2De-vig each leg's original probability

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Step 3Add probability gains for each key number crossed

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Step 4Multiply adjusted leg probabilities

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Step 5Compare combined probability to teaser payout

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Step 6If EV positive, size with Kelly

Teaser Sizing: How Much to Bet

Once you identify a +EV teaser, position sizing follows the same Kelly Criterion framework as any other bet.

Worked example: sizing a +EV 2-leg teaser

Your 2-leg 6-point teaser at -110 has a combined hit probability of 53.3%.

Step 1: Convert to decimal odds. -110 American = 1.909 decimal.

Step 2: Run Kelly. Kelly % = (0.533 x 1.909 - 1) / (1.909 - 1) = (1.018 - 1) / 0.909 = 0.018 / 0.909 = 1.98%

Step 3: Apply half Kelly. Half Kelly = 0.99% of bankroll.

On a $5,000 bankroll, that is a $49.50 bet. The edge is thin, so the sizing is small. This is correct. Teasers with true +EV rarely justify large allocations because the edges are typically 1-3%. The Kelly Criterion calculator handles decimal odds directly.

Teaser Variations and How They Change the Math

6-point vs 6.5-point vs 7-point teasers

More points cost more. A 6.5-point teaser typically pays -120 instead of -110. A 7-point teaser might pay -130.

The question: does the extra half or full point of line movement generate enough additional win probability to overcome the worse price? Usually no, unless the extra points cross an additional key number.

A leg at -7.5 teased 6 points to -1.5 crosses 3 and 7. Teasing 7 points to -0.5 adds one more number (1) but that number is not a key NFL margin. The probability gain is maybe 1 percentage point. The price increase from -110 to -130 costs you roughly 3 percentage points of break-even probability. Net effect: negative.

The exception: if the extra point crosses 3 or 7 that the shorter tease would miss. A leg at -9.5 teased 6 points to -3.5 misses crossing 3. Teased 7 points to -2.5 crosses 3. That extra point is worth 8-10 percentage points of probability. In this specific case, paying -130 for 7 points is better than -110 for 6 points.

3-leg teasers

Three legs at -110 to -120 require all three to hit. Even with strong 3/7 crossings, three legs at 72%, 71%, and 73% probability give a combined rate of:

0.72 x 0.71 x 0.73 = 37.3%

A 3-leg teaser at +150 (standard payout) needs 40% to break even. At 37.3%, it is -EV. Three-leg teasers almost never have positive expected value because the multiplicative probability decay overwhelms the improved payout.

Stick to 2-leg teasers. The math is clear on this.

NBA and other sports

Teaser value is sport-specific. NBA scoring margins do not cluster around specific numbers the way NFL scores cluster around 3 and 7. There is no basketball equivalent of the field goal or touchdown that creates exploitable probability spikes at certain numbers.

NHL, soccer, and baseball have too few total scoring events for point-buying to generate meaningful probability shifts. A 1.5-goal tease in hockey might flip the probability by 25 percentage points, but the teaser price reflects that.

NFL remains the only major sport where teasers can have structural +EV. For other sports, standard single bets sized by Kelly on de-vigged probabilities are the better approach. Read sports betting math for the foundational formulas.

Common Teaser Mistakes

Mistake 1: Teasing through dead numbers. A 6-point tease from -13 to -7 crosses 12, 11, 10, 9, 8. These are low-frequency NFL margins. You are paying full price for points that barely change your win probability. Always check which specific numbers you cross, not just how many.

Mistake 2: Adding legs for a bigger payout. Each additional leg multiplies probabilities. Going from 2 legs to 3 legs at the same per-leg probability drops your combined hit rate by 25-30%. The payout increase from -110 to +150 does not compensate. More legs always means worse EV for teasers.

Mistake 3: Ignoring the de-vigged baseline. You cannot evaluate teaser value starting from the vig-included line. A -7.5 (-110) selection has a de-vigged probability around 50%, not 52.4%. Starting from the wrong base probability cascades through every subsequent calculation. Always de-vig first.

Mistake 4: Using teasers as "safer parlays." Teasers are not safer. They are a different bet with a different price for a different probability. Calling them safer implies they have less downside, which is only true in the sense that you win more often. You also win less money per win. The EV is what matters, not the hit rate.

Mistake 5: Teasing totals. Key number theory applies to spreads, not totals. NFL totals do not cluster around specific numbers the way margins do. Teasing an over/under from 44.5 to 50.5 buys probability, but not at the concentrated rate that crossing 3 and 7 provides. Spread teasers with key number crossings are where the value lives.

When Teasers Beat Straight Bets

Teasers are not inherently better or worse than straight bets. They are a different instrument. The comparison:

Teasers make sense when: both legs cross 3 and 7, the price is -110 or better for a 2-leg tease, and you have confirmed the combined probability exceeds the break-even threshold after de-vigging. In all other cases, straight bets on individual games sized by Kelly are the sharper play.

For how this fits into a broader betting strategy, the expected value guide covers the framework for evaluating any bet type. And how does moneyline work covers the simplest bet structure that teasers are built on top of.

Frequently asked questions

Are NFL teasers profitable?

NFL teasers can be +EV when both legs cross through the key numbers 3 and 7. This means original lines between -8.5 and -7.5 for favorites, or +1.5 to +2.5 for underdogs. Outside these ranges, teasers are almost always -EV because the bought points do not cross high-frequency scoring margins.

What is the 3/7 rule for teasers?

The 3/7 rule states that teaser value comes almost entirely from crossing the numbers 3 (field goal margin) and 7 (touchdown margin). About 15% of NFL games land on exactly 3, and 9% land on exactly 7. Moving your line across both numbers provides the largest probability gain per point bought.

Should I bet 3-leg teasers?

Almost never. Three legs at 72% individual probability give a combined 37.3% hit rate. The standard +150 payout requires 40% to break even. The multiplicative probability decay across three legs overwhelms the improved payout in nearly all cases. Two-leg teasers at -110 are the only structure with consistent +EV potential.

How do I size a teaser bet?

Use the Kelly Criterion on the teaser's combined probability and payout odds. A 2-leg teaser at -110 with 53.3% combined probability produces a Kelly recommendation of about 2% of bankroll. Apply half Kelly for a 1% allocation. Teaser edges are thin, so small sizing is correct.

Do teasers work in the NBA?

NBA teasers rarely have +EV because basketball scoring margins do not cluster around specific numbers the way NFL margins cluster at 3 and 7. Without key number crossings that generate outsized probability gains, the price of bought points exceeds their value. Stick to NFL for teaser value.