What is max pain in options?

The calculation, step by step

Start with every strike in a single expiration and its open interest for calls and puts. Then pick a candidate settlement price. For each call strike below that price, the calls are in the money by the difference, so their total value is the difference times the call open interest times the contract multiplier of 100. For each put strike above the candidate price, the puts are in the money by the difference, valued the same way. Out-of-the-money options contribute zero.

Add up the call value and the put value at that candidate price. Repeat for every strike on the board as a candidate. The candidate with the lowest total is max pain. That is the whole method. There is no model, no volatility input and no assumption about who owns what, which is part of why the number is so widely published.

Because the calculation uses only open interest, it is usually built from the previous night's figures, and it can shift as positions open and close during expiration week. On heavily traded names it often moves by a strike or two between Monday and Friday.

A small worked example

Imagine a stock with three strikes for Friday: 95, 100 and 105. Calls: 1,000 at 95, 4,000 at 100, 6,000 at 105. Puts: 6,000 at 95, 3,000 at 100, 500 at 105. Settle at 95: the 100 and 105 puts are in the money by 5 and 10, worth 3,000 times 5 plus 500 times 10, or 20,000 before the 100-share multiplier, so 2,000,000 dollars in total. No calls are in the money.

Settle at 100: the 95 calls are worth 5 times 1,000, and the 105 puts 5 times 500, a combined 7,500 before the multiplier, or 750,000 dollars. Settle at 105: the 95 calls are worth 10 times 1,000 and the 100 calls 5 times 4,000, a combined 30,000, or 3,000,000 dollars, with the 95 and 100 puts worthless. The lowest total is at 100, so 100 is max pain for that expiry.

Notice what drives the answer: max pain lands where heavy put open interest above it and heavy call open interest below it are both minimized. It usually sits near the middle of the open interest distribution, which on most names also means near the current price.

Why traders watch it

The theory behind max pain is that option sellers, collectively, benefit if the underlying settles there, and that hedging around large expirations can drag price toward it. That theory is contested, and there is a separate article on whether it holds up. What is not contested is that max pain is a convenient summary of where open interest is centred for a given expiry.

Used that way, it is a reasonable reference point, much like the call wall or put wall. Every ticker's page at flowmonkey.net/levels shows its call wall, put wall and max pain from the closing book, so you can see all three side by side rather than treating any one of them as the answer.

Max pain next to the walls

It helps to see how max pain relates to the other levels drawn from the same open interest. The call wall and put wall are about gamma: they mark where estimated dealer hedging pressure is heaviest above and below price, and they depend on a volatility input and an assumption about which side the dealer holds. Max pain is about payout: it marks where the intrinsic value owed to holders is lowest, and it needs neither.

In a typical book, max pain lands between the put wall and the call wall, because heavy puts below and heavy calls above both push the minimum toward the middle. When it does not, for example when max pain sits well below the put wall, that usually means the open interest is lopsided, with a large block of in-the-money calls left over from an earlier rally. That is worth knowing on its own, as a description of how the book was built, even though it says nothing about where price goes next.

Common mistakes

The most common mistake is mixing expirations. Max pain is defined per expiry; blending weekly and monthly contracts produces a number that does not correspond to any settlement event. Another is ignoring that open interest is a snapshot from the prior close: a strike that looks dominant on Monday may have been half closed by Thursday.

The last is reading max pain as a target. It is the price where a calculation reaches its minimum, not a price anyone is obliged to defend.