This page is loading — it needs JavaScript. The written page below is served without it.
A strikeout prop is an over/under on how many batters one pitcher strikes out in one game. It is the most-priced pitching market in baseball, it behaves differently from every other player prop on the board, and most of what makes it different is about when it appears and what the game log behind it can honestly say.
The book posts a number for a named pitcher in a named game and offers both directions on it. The bet settles on the strikeouts he records in that game and on nothing else — not the result, not the innings, not the earned runs. It is one line in the box score, which is what makes the market so easy to price and so easy to check afterwards.
That also means the number is a half-point more often than not, for the same reason every other prop line is: a whole number leaves a push on the table and the book would rather settle the bet. Strikeouts are whole events, so a line quoted at a half is asking a genuine question about the count either side of it.
Sportsbooks price a strikeout market for the two announced starters and for nobody else. A reliever never gets a strikeout number, because nobody knows whether he will appear. So the market cannot exist before the rotation does, and for a game two days out there is usually nothing to read.
The useful consequence runs the other way. If a pitcher is carrying a posted strikeout line for tonight’s game, he is starting it — the market is the announcement, as the books currently understand it. This site reads probable starters exactly that way rather than from a rotation guess, and shows nothing for a game where no strikeout market has been posted yet. An empty pitching panel in the morning is the book waiting on a lineup card, not a broken page.
It is also why a baseball prop board fills later in the day than a basketball one. Books wait on lineups for MLB, the strikeout market is the first pitching market to arrive, and everything downstream of it — the measured history, the comparison across books — only has something to attach to once it exists.
Most player props are effectively a one-way market: the over is posted everywhere and the under is thin, late or missing, so a reader who thinks a number is too high often has nothing to do about it. Pitcher strikeouts are one of the few families where books routinely post both directions at the same number, and paired with them is the hits-allowed market on the same pitcher.
That matters for reading rather than for betting. A market quoted on both sides is a market where the number in the middle is doing real work, because the book is exposed in both directions and has to place it where the money balances. A one-way market tells you much less about where the book thinks the true count sits.
A starting pitcher works about every fifth day. A last-five window in baseball is therefore roughly a month of calendar, where a last-five for a basketball player is about ten days — the same phrase describing two very different amounts of recency. A full season of starts is a smaller sample than most people expect, and the usual warning about small denominators applies harder here than anywhere else on this site.
The second way is a limitation of the data itself, and it is stated here rather than left to be discovered. The box scores behind these pages carry a pitcher’s strikeouts and hits allowed and no innings, outs or games-started column. There is no way in that data to separate a six-inning start from a one-inning relief appearance, so a count that called itself "last five starts" would be wrong in a way the reader could not see. Every pitching count on this site says appearances, means appearances, and prints the number it counted.
How deep a pitcher is allowed to go is a decision somebody makes during the game, and it is not in the game log. A pitcher pulled early on a pitch count, in a blowout, or because his manager is protecting an arm records the strikeouts of a short outing regardless of how he was throwing. That is the single largest source of variance in this market and no history column contains it.
The opposing lineup is the other half. Strikeouts are a two-sided event and the batters have as much to do with the count as the pitcher does, which is why a measured history against one opponent is worth reading in the direction of "is there anything here at all" rather than as a precise number — those splits are usually a handful of games and this site prints their game counts for that reason.
So the honest version is a description and not a recommendation. Parlay Builder measures what a pitcher has done at every threshold his own log supports, shows what the books are asking for it and how old that price is, and stops there. It does not accept wagers, hold funds or settle bets, and past performance does not predict future results.
An over/under on the number of batters one pitcher strikes out in one game. It settles on that single line of the box score and on nothing else — not the result, not innings pitched, not runs allowed — which is what makes it simple to check after the fact.
Once the starting pitchers are announced, which for baseball is usually the day of the game. Books price the market for the two announced starters and for nobody else, so a game two days out generally has no strikeout market at all and a board that looks empty in the morning is waiting on lineup cards.
Usually, yes — pitcher strikeouts are one of the few player prop families where books routinely post both directions at the same number, alongside the hits-allowed market on the same pitcher. Most other props are offered one way in practice, with the under thin or missing.
Because the box scores behind these pages carry strikeouts and hits allowed and no innings, outs or games-started column, so a six-inning start and a one-inning relief outing are the same row. Calling a mixture of the two "last five starts" would be wrong in a way a reader could not detect, so the label says what the count actually counted.
The measured history is built from thresholds in the pitcher’s own game log, so it stays true after the line moves and can be rebuilt nightly from box scores. Anything compared against a posted number is loaded live from the board instead, because a cached page cannot honestly describe a price that changed at lunchtime.
A starter works about every fifth day, so a last-five window covers roughly a month of calendar rather than the week or two the same phrase means in basketball. Denominators are small, splits divide them further, and every rate on this site is printed with the number of games it was measured over for exactly that reason.
Every prop the books have posted, each with the measured history and the game count behind it. See tonight’s posted strikeout markets.
You must be 21+ (or older, where your jurisdiction sets a higher age) to bet. If gambling stops being fun, call or text 1-800-GAMBLER for free, confidential help. All guides.
Odds and lines come from licensed data feeds and refresh on a schedule; hit rates, edges and grades are Parlay Builder’s own calculations.