An NFL game simulator plays the game out thousands of times before kickoff and keeps the box score from every run: who won, who scored, whether your bet cashed. Count those up and you've got a hit rate you can put next to the book's price.
Ours is called the Sims, and our sister site Stokastic built it. It plays every NFL game 10,000 times before kickoff, with a full box score from every run. Ask The Sims is the free box on top. You type the bet in plain English, and it tells you how often it hit, with the DraftKings or FanDuel price next to it.
Tap the box below and it opens Seahawks-Broncos from Week 6 in the simulator, so it matches every example on this page.
Every number on this page comes from the Sims run Tuesday, Oct. 13, at 7:47 p.m. CT, with FanDuel and DraftKings prices from about 7:55 p.m. CT. FanDuel parlay prices are the tool's estimates; the real quote shows when you build the ticket. For any other game, open the DraftKings simulator or the FanDuel simulator.
The Parlay Hits Twice as Often as the Math Says
Every answer card has the same layout: the Sims' hit rate on the left, the book's price next to it and a grade at the bottom (good value, fair or negative).
The Week 6 ticket is Seahawks at Broncos: Seattle wins, Jaxon Smith-Njigba scores and Sam Darnold throws 2+ touchdowns. Plug the three FanDuel prices (-152, +105 and +120) into a parlay calculator and it gives this about a 13% chance, which works out to +647. FanDuel's app doesn't pay anything close to that for a same game parlay.
The calculator pretends the three legs are independent. They aren't, because Darnold throwing two touchdowns and Smith-Njigba scoring come from the same game script. In the Sims where Darnold throws 2+ touchdowns, Smith-Njigba scores 78% of the time and Seattle wins 71% of the time.
The Sims just count it: all three legs hit in 2,578 of the 10,000 games, or 25.8%. That's about twice what the calculator says.
FanDuel prices that correlation into its same game parlays, so the app cuts the payout from +647 to somewhere around +363.
Turn that 25.8% into odds and you get +288, the break-even price. Even after FanDuel's cut, +363 pays more than that, which is why the card grades it good value.
The card also grades every leg alone. The Seahawks moneyline comes back as negative value, meaning -152 costs more than Seattle's chances are worth (the Sims make it about -133), so I asked the Sims about the ticket without it. Smith-Njigba scoring plus Darnold throwing 2+ hits 36% of the time, which is worth +178, and the tool expects FanDuel at about +220 for it.
Both tickets grade out as good value. Adding Seattle drops the hit rate from 36% to 26% for a bigger payout, and which one you bet is your call.
What an NFL Game Simulator Tells You
Nobody can tell you the final score. The most common exact score in the Sims shows up 1% of the time, so if someone tells you it'll be 23-20, they're guessing.
The Sims can tell you how often each team wins. Seattle wins 57% of the 10,000 games, Denver wins 42% and the other 1% end tied. The typical final is 21-20.
That 57% is worth about -133, and FanDuel charges -152. So the Seattle leg graded out as negative value in the parlay above.
Smith-Njigba Scores 53% of the Time
Smith-Njigba's anytime touchdown is +105 at DraftKings and FanDuel. At that price he has to score 48.8% of the time for you to break even.
He scored in 53% of the Sims, which makes the bet worth -113. Plus money on a guy who scores more often than not is exactly what I'm looking for, and I'd take +105 at either book. He still gets shut out in 47% of the Sims, so I'd bet it at normal size. He's also questionable with an ankle injury and was limited at practice Tuesday, so if he's ruled out, the Sims re-run without him and this number changes.
One Prop, Two Prices
George Holani over 14.5 receiving yards is +201 at DraftKings and +178 at FanDuel. OddsShopper's job is finding you the +201 instead of the +178.
The Sims tell you if even the +201 is worth a bet. They have Holani clearing it 36.2% of the time, which makes the bet worth about +176. DraftKings pays more than that and FanDuel's +178 sits right on the number, so I'd only bet it at DraftKings.
When the Sims and the Books Disagree
Big gaps are where I trust the Sims least.
Courtland Sutton is +240 to score at FanDuel, which works out to about 29%. The Sims have him at 19.4%, so on paper that's a big gap in the book's favor. But when the Sims and the books are 10 points apart, I don't trust the gap in either direction. The people betting it may know something the Sims don't, like a practice report or a change in who gets the red-zone looks.
We built Ask The Sims to back off in exactly this spot. Any gap over 10 points, either way, gets flagged, and the tool makes no value call. No call means I don't bet it.
Watch the injury report before you bet. The Sims only know the lineup news that's in at the time of the run, so if a starter is ruled out before kickoff, wait for the Sims to re-run and ask again.
Ask Your Own Question
None of this math is on you. Open the simulator for the book you use. It has every game on this week's slate, with the next kickoff pulled up first.
Then pick a game and type it the way you'd say it. All three of these work in the full simulator. The box at the top opens on Seahawks-Broncos.
- "How often does Puka Nacua score and the Rams win?"
- "Best 3-leg parlay if the Chiefs win"
- "Josh Allen 250+ passing yards and 2 TDs"
If you're trading Kalshi or Polymarket instead, you can ask the same questions against Kalshi and Polymarket prices.
Ask the Sims the bet you were already going to make this week.
More on this: Simulation Betting 101: Find Value in NFL Props and Parlays · Parlay Betting Explained: The +EV Fix For Your Slip · How To Bet NFL On DraftKings: A Beginner's Guide · How To Bet NFL On FanDuel: A Beginner's Guide
