Finding arbitrage
What an arbitrage opportunity is, how to read the board, and why speed matters when prices align across books.
What an arbitrage is
An arbitrage — commonly called an "arb" — is a matched bet where you back every outcome of the same market across two different sportsbooks, and the combined stakes are structured so that, if both bets are placed at the displayed prices and settle, the matched bet is designed to return a profit on either outcome. Unlike positive EV betting, which requires a large sample before the math shows up in your results, a successfully executed arb is structured to return a small profit on that event alone, when both legs are placed at the shown prices and settle as expected.
The condition that makes a market arbable is simple. Express each book's offered price as an implied probability — that is, divide one by the decimal odds for each side. When those two implied probabilities add up to less than one, the books together are pricing the market at less than 100%, and the gap is the modelled profit margin. In formula form: when 1/o₁ + 1/o₂ < 1, the market is arbable.
The figure the Arbitrage Finder uses to rank and filter these opportunities is called arbValue: the sum 1/o₁ + 1/o₂. Because a lower total means a wider gap below 1, a lower arbValue is better. The board is sorted with the strongest arbs — the lowest arbValues — at the top.
The feed
The Arbitrage Finder scans across 70+ sportsbooks, exchanges, and DFS sites and surfaces every qualifying matched bet in real time. Each card on the board shows:
- The event and market (team, market type, game time)
- Two bet sides — one per book — each with the book's logo, the selection name, the current price, and a recommended stake
- A profit badge expressed as a percentage of total stake
- A direct link to open both books simultaneously
Taking a matched bet creates two independent wagers in your tracker — one for each side. They are not grouped into a single unit; the Bet Tracker treats them as separate bets that each settle on their own outcome.
The board updates as odds change — live prices arrive in near-real-time for some books and within about four seconds for others; in pregame mode you can set a manual or timed refresh. Because arbs are created and destroyed by normal line movement, a card that was profitable when you saw it may be gone — or no longer profitable — within seconds. Acting quickly matters more here than in any other tool. In Live mode, an arb whose Market View you have open stays in its place on the board while you look at it, and its prices, stakes and profit keep updating from the live market. It is only marked stale once the arb is gone, for example because the prices no longer add up to a profit or one of the books stops offering its side. A stale arb's leg prices and stakes turn grey, both on the card and in its full-screen view on a phone. Once you close the Market View, the card follows the board again.
The board opens in Pre-game mode. To switch to Live, use the Pre-game and Live tabs in the header above the board on a tablet or computer, or the mode selector at the top of the page on a phone. Switching to Live starts streaming straight away.
The green button at the start of the header above the board controls updates. In Live mode it pauses and resumes the stream: pause to freeze the displayed bets, then press play to resume, which loads the current board. In Pre-game mode with a timed refresh it pauses and resumes the timer, and with a manual refresh it becomes a Refresh button that reloads the board once. On a keyboard, the Space bar does the same as the pause and play button. The line under your bet size shows whether the board is streaming, paused, or when it last updated.
Verify before you bet
A very high profit percentage — anything that looks unusually large — is worth double-checking at the book before placing either side. Data delays or a line correction at one book can make an arb appear bigger than it is. If you are unsure, ask in the community Discord before committing.
Middles
A subset of the Arbitrage Finder results are middles: matched bets where the two sides cover a spread or total gap rather than strict opposing outcomes. If the final result lands inside the gap, both sides win and you collect on both legs. If it falls outside the gap, one side loses — but the middle is still structured so the worst case is a small, bounded loss rather than a full-stake loss.
The Middles filter lets you show arbs only, middles only, or both. Middles are covered in depth at Middles: win both sides.
Filters
Your bet size is shown at the top of the board, next to the update button (for example "$200 bet size"). Tap it to change it: from tablet width up you edit it in place, and on a phone it opens a small panel with Save and Cancel. SmartStake uses this to calculate the recommended stake for each side of every arb so the profit percentages reflect your actual exposure. The full set of filters — sportsbooks, leagues, markets, arb percentage range, minimum bet size, date range, and the middles toggle — is covered in Arbitrage filters.
You can save filter configurations and set up to five alerts on them from the bell beside the settings button, so a push notification tells you when a new arb matches and you do not need to watch the board continuously. See Saved filters and alerts.
Next steps
Once you find an arb you want to act on, open the card to see the full stake breakdown and profit calculation, then head to Reading the matched bet card and Placing both sides. For definitions of any term used here, see the Betting glossary.
- Odds, prices, expected value, conversion rates, and profit figures shown are estimates based on the last data we retrieved. They can change at any time — confirm the current price at the book before you bet, as odds may move and entry errors can occur.
- Arbitrage and matched betting carry execution risk: a price can move or a leg can be rejected before you place both sides, and sportsbooks may limit or void bets. A favorable outcome is not guaranteed.
- Using a “sharp” book as a fair-value reference is a modeling choice, not a statement of accuracy. Review a book’s record yourself and anchor on the books you trust.