StackLab

Why the number isn't a multiply

Legs out of one game aren't independent. A quarterback's passing yards and his receiver's are the same drives counted twice — when one goes over, the other usually does too. Multiply six chalk overs as though they were separate games and the slip looks better than it is.

So StackLab doesn't multiply. Every game here is simulated 20,000 times, and each posted line carries a record of which runs it hit. The chance a whole slip lands is the share of runs where every leg hit at once. That number is usually higher than the multiply for overs that rise together, and lower for legs that fight each other — a back's rushing yards against his own quarterback's passing yards, say.

What the EV number means

EV is our win probability times what the slip pays, minus one. Positive means our model makes the parlay worth more than it costs. Negative means the book is ahead of us, and that's the common answer — it should be. Books hold a margin on every leg, and a parlay multiplies it.

Which is also why the leg-count strip matters. Inside a fixed payout band, each extra leg multiplies the same hold again, so EV falls as the count rises. We measured that on 167,255 real slips built from closing prices: −18.0% at three legs and −29.2% at six, before any model at all. The strip shows the same shape on the pool in front of you.

Every leg here has a book number beside it

A book quotes some props one way only — the over, never the under. With one side there's no way to strip the book's margin out, so there's no honest number to set ours against, and a leg like that sat in the pool with a dash where the comparison goes. The deep alt rungs are out for that reason. The pool line at the top of the table counts what got dropped.

Anytime touchdown stays, and it's the one exception. We hold 713,433 touchdown quotes and not one “no” — nobody prices that market both ways, so it's a dash for everyone, not thin coverage. It's also the most-bet prop in football. The EV beside it is still real: that number is our chance times what the price pays, at a price a book is posting right now, and only the comparison column goes missing. On the week we checked, all 14 anytime-TD legs on the slate came out negative, the best of them at −3.9%. Take one because you want it, not because the sort put it there.

One book at a time

A same-game parlay only exists inside one sportsbook, so the pool is one book's own quotes and the payout is what that book's legs multiply to. Real books also re-price correlated legs on an SGP, usually downward — so treat the payout here as what the singles come to, not as a quote.

Legs run from +100 to −1200. Nothing deeper than −1200, because depth buys hold and nothing else — per-leg returns sit flat at about −5% the whole way from a coin flip to 97%. The near-even end is open on purpose. When we measured a real board, 51 of its 53 chalk legs came out negative and the one slip that finished ahead was carried by a −125 leg. The value is at that end, not up the ladder.

A tool, not a tip. MatchWiz has no measured edge on NFL player props, and this page will tell you when a build is negative rather than hide it. Nothing here is betting advice. 21+.