Liquidity in one line
A stock or option is liquid when many buyers and sellers are active, so you can trade quickly at a price close to the last traded price.
How to see it
- Volume: how many shares or contracts traded. More volume usually means more liquidity.
- Bid–ask spread: the gap between the best buy and best sell price. Narrow spreads mean lower trading costs.
- Market depth: how many orders are waiting at each price. Deep order books absorb large orders with less price movement.
- Open interest (for F&O): how many contracts are open — see open interest.
Why it matters
In illiquid stocks or far out-of-the-money options, the spread can be wide, so you may buy noticeably above and sell noticeably below the fair price. Index options such as NIFTY near the current price are among the most liquid contracts in India.
"Liquidity zones" in price-action trading
Some traders use "liquidity" to mean areas where many stop-loss or pending orders are likely to sit — for example just above a clear swing high or just below a swing low. Price sometimes moves through such levels quickly and then reverses. This is an interpretation of the chart, not something the exchange publishes, and it does not predict the next move.