Tick size is the minimum price difference that must exist at all times between consecutive bid and offer prices. For example, if a stock has a tick size of ₹0.05 and the last traded price (LTP) was ₹100, then the next five best bid prices for the stock would be ₹99.95, ₹99.90, ₹99.85, ₹99.80, and ₹99.75. In this instance, the bid price cannot be ₹99.87, as it does not meet the tick size requirement of ₹0.05.