Why do parlays favor the sportsbook?

Every leg carries the book's margin, and multiplying legs multiplies the margin. A typical -110 leg holds about 4.5% — six of them compound to roughly 24% of every dollar, which is why books promote parlays harder than any other bet.

What is the fair price of a parlay?

Strip the vig from each leg to get its true probability, multiply the probabilities, and convert back to a price. The gap between that fair price and the payout offered is exactly what the book keeps.

Are singles better than parlays?

For the same total stake, singles pay the market's margin once per bet while a parlay pays it on every leg simultaneously. Parlays buy variance — a small chance at a big number — at a measurably worse price.

⚖️ The Truth Machine · what your parlay is really worth

The books love your parlay. Here’s exactly how much.

Enter the legs of any ticket. The machine strips the vig, computes the fair price, shows what the book is keeping — and what the same money would do as singles. Every league, every book, all math on your phone.

Leg price

Label (optional)

Leg price

Label (optional)

Stake $

Assumed hold per leg

Hold per leg = the margin baked into each price (a standard -110/-110 market holds ~4.5%). The machine removes it to find each leg's true probability.

What this tool does — and why it matters ▾

Every sportsbook builds a margin into every price — and a parlay pays that margin on every leg at once. The Truth Machine is a vig X-ray: it strips the margin out of each leg, rebuilds the ticket at its fair price, and shows the gap in plain dollars.

Fair price, exposed. Each leg’s true probability is recovered by removing the book’s hold, then multiplied across the ticket — the price the parlay should pay.
The keep bar. One glance shows your share of fair value versus the slice the book keeps — the number they never print on the slip.
Expected value in dollars. Not theory — the actual long-run cost or profit of this exact ticket at your stake.
The singles mirror. The same legs, the same money, bet separately — and the exact dollar difference over the long run. Parlays buy a lottery shape; this shows the ticket price.
Adjustable hold. Sharp books hold less, promos hold more — set the margin per leg and the machine recalculates everything.
Every league, every book, forever. Pure math, computed on your phone. Nothing is sent anywhere, nothing expires, nothing needs a login.

This math runs live on every game, automatically.

FantasyDailies scans 9+ sportsbooks all day — risk-free locks, best price on every line, player prop wars — free, no signup.

Member accounts with saved bets, alerts and premium tools are coming — the list goes first.

Accounts are coming

The books love your parlay. Here’s exactly how much.

The same money, as singles