Once you start reading about options, three little abbreviations show up everywhere: ITM, ATM, and OTM. People throw them around like you are supposed to already know them, and most beginners just nod along. Let's actually learn them, in plain English, assuming you know nothing. They sound technical. The idea behind them is genuinely simple.
Together these three words are called "moneyness." All moneyness means is one thing: how far the option's strike price is from where the market actually is right now. That is the whole concept. Everything below is just detail.
The one rule behind all three
Every option has a strike, the price level you are betting on, and the market has a current price (say Nifty at 22,000). The only question moneyness answers is this: if you could cash this option in right now, would it be worth anything?
If yes, it has real worth right now, and that is in-the-money. If it is basically sitting at the current price, that is at-the-money. If it would be worth nothing today, that is out-of-the-money. That is it. ITM has real worth, OTM has none yet, ATM is sitting on the line.
ITM, ATM, OTM for a call (with a real Nifty example)
Remember a call is a bet that the price goes up: it is the right to buy at the strike. Say Nifty is at 22,000 right now.
In-the-money (ITM) call: a strike below the current price, like the 21,800 call. It lets you buy at 21,800 while the market is at 22,000, so it is genuinely worth about 200 points right now. That is real worth. ITM calls cost more, because you are paying for that real worth.
At-the-money (ATM) call: the strike sitting right at the price, the 22,000 call. It has almost no real worth yet, but it is right on the edge. This is the one most active traders use.
Out-of-the-money (OTM) call: a strike above the current price, like the 22,300 call. The right to buy at 22,300 is useless while the market is at 22,000, so it has zero real worth today. It is pure "maybe." That is why it is cheap.
Puts are just the mirror
A put is a bet that the price goes down, the right to sell at the strike, so moneyness flips. For a put, ITM means a strike above the current price (you could sell high while the market is low, so it has real worth). OTM means a strike below the price (useless today). ATM is the same as before, sitting on the current price. Same idea, opposite direction. You do not need to memorise it. Just ask "would this be worth anything right now?" and the answer tells you.
Why the cheap OTM option is a trap
Here is the part the textbook definitions skip, and the part that empties beginner accounts.
That OTM 22,300 call costs almost nothing, maybe ₹40, while the ITM 21,800 call costs ₹250. The cheap one feels safer: less money at risk, more lots for your budget. It is the opposite of safe. Because it has zero real worth, an OTM option is made entirely of "maybe," and that maybe is time value, which melts a little every single day until expiry, called theta. If the market does not move far enough fast enough, an OTM option does not just lose some value, it goes to zero.
This is why so many beginners can be right about direction and still lose: they buy cheap OTM options, the move comes too slowly, and the premium drains out from under them. Cheap does not mean low risk. With options, cheap usually means unlikely. That whole "real worth versus maybe" split is the premium, explained here.
So which one should a beginner buy?
The honest answer: lean toward ATM or slightly ITM, and treat deep OTM options as the lottery tickets they are.
ATM and slightly-ITM options move more reliably with the market and are not pure time value, so you are not fighting a clock that is guaranteed to win. They cost more per trade, which is exactly why beginners avoid them and reach for the cheap OTM strikes instead. That instinct, "the cheap one, so I can buy more," is the single most common way new options buyers donate money to the market.
It is not really a knowledge problem, it is a behaviour one. The cheap strike is most tempting exactly when you are chasing a move or trying to win a loss back fast. That chase is FOMO, and it lives in your trade history. SubTrades spots these patterns in your own tradebook.
Where you actually see this
Moneyness is exactly what you are looking at when you open the option chain: the strikes near the current price are ATM, the ones with real worth are ITM, and those long rows of cheap, far-out numbers are OTM. Now when you see them, you will know which is which, and which one is quietly working against you.
The one thing to remember
Moneyness is just distance from the price. ITM has real worth and costs more. OTM has none yet and looks cheap. ATM sits on the line. The cheap OTM option is the most tempting and the most likely to expire at zero, so the "affordable" choice is usually the expensive mistake. When in doubt as a beginner, stay near the money and respect the clock.
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