Calculator

Teaser Calculator

About this calculator

By Alex Thornton · author of the MIT-licensed teachersbettextbook library · Last reviewed 24 July 2026

A teaser sells you points and charges for them in payout. This prices the trade.

The same ticket without the points bought: the parlay calculator →

A teaser moves every leg’s spread or total a fixed number of points in your favor, and charges you a much shorter price for the help. The calculator shows what each leg has to win for the ticket to break even.

What you are actually buying

Move every leg six points your way and the combined price gets much shorter. The only question is whether those points bought more probability than the price gave up.

A two-team six-point teaser at −110 needs each leg to win 72.37% of the time. That is the bar, and it is a lot higher than it feels.

Whether you clear it depends almost entirely on which numbers you cross. Crossing 3 and 7 in football is worth real probability. Moving from 11 to 17 is worth very little.

You can also check it without estimating anything: compare the teaser against simply buying those same numbers straight.

Want more math?the Nerd Corner

p_{\text{ticket}} = \dfrac{1}{d_T}, \qquad w = \left(\dfrac{1}{d_T}\right)^{1/n} = d_T^{-1/n}

where:

$d_T$ : the teaser’s decimal odds, total return per dollar including stake. −110 is $d_T = 1.9091$ ; +150 is $d_T = 2.50$ .
$n$ : the number of legs, 2 or more. Every one must win, exactly like a parlay.
$p_{\text{ticket}}$ : the break-even chance for the whole ticket, vig included.
$w$ : the break-even win rate per leg, assuming equally likely, independent legs.
$q_B = 1/d_B$ : the break-even of the same leg at its untouched number. At −110, $q_B = 52.38\%$ .
$w - q_B$ : the probability the points must buy, in points of win probability per leg.

Worked example: the numbers in the form below

A two-team six-point teaser priced at −110, built from legs that were posted at −110 before the tease:

d_T = 1.909091 \;\Rightarrow\; p_{\text{ticket}} = \tfrac{1}{1.909091} = 52.38\%

w = 0.523810^{1/2} = 72.37\%, \qquad q_B = 52.38\%

w - q_B = 72.37\% - 52.38\% = +19.99\ \text{probability points per leg}

Two −110 legs parlayed straight pay 3.6446; teased six points they pay 1.9091, 47.62% less. So the six points have to lift each leg by roughly 20 probability points just to match the parlay they replaced. Whether any particular six points do that is a question about where final margins land, not one this arithmetic can answer.

How a teaser is priced

One American number covers the whole ticket, so inverting it gives the chance the ticket must hit; the n-th root splits that across the legs. The root is what makes teasers deceptive. A three-team teaser at +150 sounds long (the ticket need only hit 40%) but that is 73.68% per leg. Adding the third leg drops the ticket break-even 12.38 points while raising the per-leg requirement 1.31.

Where the points come from: 3 and 7

Not all six-point moves are equal, and the reason is the shape of the margin distribution rather than anything in the price. NFL final margins cluster on 3 and 7 (the field goal and the touchdown-plus-extra-point) far more heavily than on any other number, so a move across both spikes collects more probability than the same move across a flat stretch.

A −8 favorite teased to −2 crosses both. A −13 teased to −7 crosses only flat numbers and stops on 7, where a margin of exactly 7 is a push rather than a win.

What this page will not do is tell you that any of those clear 19.99 points. That is an empirical question about a margin distribution, measured season by season from actual final margins: the 2015 extra-point change moved the curve. An edge quoted without naming its sample has no denominator.

Instead it prints $w$ , prints $w - q_B$ , and takes your own estimate of the post-tease win rate as an input, so the expected value is a function of your number rather than ours. At the break-even rate it prints $0; two-thirds of a point either side flips the sign.

The check that needs no estimate

If the book posts a straight price on the teased number (the alternate line), then parlaying those alternate lines is the same bet as the teaser, so the two prices can be read side by side:

\text{straight parlay of the teased numbers} = \prod_{i=1}^{n} d_{A_i} \quad\text{vs}\quad d_T

Worked example: teaser vs alternate-line parlay

Two legs teased six points, priced as straight bets at −265 and −245. The teaser is −110.

d_{A_1} = 1.377358, \quad d_{A_2} = 1.408163 \;\Rightarrow\; d_{A_1} d_{A_2} = 1.939546

\dfrac{d_T}{d_{A_1} d_{A_2}} = \dfrac{1.909091}{1.939546} = 0.98430 \;\Rightarrow\; \text{the teaser pays } 1.57\% \text{ less}

Same outcomes, same two numbers, two prices: a 1.57% gap in favour of the alternate-line parlay; flip the alternates to −280 and −260 and it reverses. The test is pure price comparison, so it inherits nobody’s opinion about margins. Books do not always post alternate lines that far out, and those prices carry their own margin: strip it first.

Common mistakes

Teasing through nothing, or onto a key number. Six points across a flat stretch buys much less than six across 3 and 7, and landing exactly on 3 or 7 turns the most common margins into pushes, which books grade differently.
Ignoring correlation. Two legs in the same game are not independent, and the $w^n$ step assumes they are.

Check this number yourself

moneyline_to_odds is public in the MIT-licensed teachersbettextbook package; the teaser math is one reciprocal and one root on top:

pip install teachersbettextbook

from teachersbettextbook import moneyline_to_odds

n       = 2
d_T     = 1 + moneyline_to_odds(-110)   # 1.9090909...
ticket  = 1 / d_T                       # 0.5238095...
per_leg = ticket ** (1 / n)             # 0.7237470...
q_base  = 1 / (1 + moneyline_to_odds(-110))
must_buy = per_leg - q_base             # 0.1999375 -> 19.99 points

Same inputs, same digits, no account required. What is open and what is not.

Frequently asked questions

What is a teaser bet?

A teaser is a parlay in which every leg’s spread or total is moved a fixed number of points in the bettor’s favor, in exchange for a much shorter combined price. Every leg still has to win.

What win rate does a teaser leg need?

The reciprocal of the teaser’s decimal odds, raised to the power 1/n for n legs. A two-team teaser at −110 breaks even at 52.38% per ticket and 72.37% per leg; a three-team teaser at +150 needs 73.68%.

How much do the teaser points have to be worth?

The difference between the teased break-even and the untouched leg’s. Legs at −110 need 52.38% straight and 72.37% inside a two-team teaser, so six points must add about 19.99 probability points per leg, a question about the margin distribution, which this page does not assert.

Why do the key numbers 3 and 7 matter in NFL teasers?

NFL final margins cluster on 3 and 7 far more heavily than on any other number, so a move across both collects more probability than one of the same size elsewhere. A tease that stops on 3 or 7 converts wins into pushes.

What happens if a teaser leg pushes?

It depends on the book’s rule: some void the ticket and refund the stake, others drop the teaser one leg and re-price it shorter, a few grade the push as a loss. The formula on this page assumes no pushes.