Support and resistance are two foundational concepts in technical analysis. Understanding what these terms mean and their practical application is essential to correctly reading price charts.
Prices move because of supply and demand. When demand is greater than supply, prices rise. When supply is greater than demand, prices fall. Sometimes, prices will move sideways as both supply and demand are in equilibrium.
What Is Support?
In a downtrend, prices fall because there is an excess of supply over demand. The lower prices go, the more attractive prices become to those waiting on the sidelines to buy the shares. At some level, demand that would have been slowly increasing will rise to the level where it matches supply. At this point, prices will stop falling. This is support.
What Is Resistance?
Resistance is the opposite of support. Prices move up because there is more demand than supply. As prices move higher, there will come a point when selling will overwhelm the desire to buy. This happens for a variety of reasons. It could be that traders have determined that prices are too high or have met their target. It could be the reluctance of buyers to initiate new positions at such rich valuations. It could be for any other number of reasons. But a technician will clearly see on a price chart a level at which supply begins to overwhelm demand. This is resistance.
The Basics
Support and resistance can be found in all charting time periods; daily, weekly, monthly. Traders also find support and resistance in smaller time frames like one-minute and five-minute charts. But the longer the time period, the more significant the support or resistance. To identify support or resistance, you have to look back at the chart to find a significant pause in a price decline or rise. Then look forward to see whether a price halts and/or reverses as it approaches that level.
Let’s imagine that Jim notices that the price fails to get above $39 several times over several months, even though it has gotten very close to moving above that level. In this case, traders would call the price level near $39 a level of resistance. As you can see from the chart below, resistance levels are also regarded as a ceiling because these price levels represent areas where a rally runs out of gas.
Support levels are on the flip side of the coin. Support refers to the price level on a chart where equilibrium is reached. This means that demand has increased to match supply. This causes the decline in the price of the asset to halt; therefore, price has reached a price floor. As you can see from the chart below, the horizontal line below price represents the price floor. You can see by the blue arrows underneath the vertical line that price has touched this level four times in the past. This is the level where demand comes in, preventing further declines. This is support.
Source: Investopedia, Support and Resistance Basics, accessed 27 December 2023, <https://www.investopedia.com/trading/support-and-resistance-basics/>