Dynamic support and resistance levels are useful technical analysis tools. They mark places where a move may stall or turn, with no guarantee that it will, and unlike a horizontal line drawn through last month's high they move with the market. Read with some care, they tell a trader where buying or selling makes sense relative to the trend, instead of chasing a move that has already happened.
This article explains what dynamic support and resistance are and covers the three most common ways to get them on a chart: moving averages, trendlines and Bollinger Bands.
What Support and Resistance Are Used For
Pivot points are one way of calculating support and resistance from the previous session's high, low and close, but the concept is broader than any single formula. Support is a price level below which an asset, even in a downtrend, has struggled to fall. Resistance is a level above which an asset, even in an uptrend, has struggled to rise. Both are places where enough buyers or sellers once turned up to stop the price, on the assumption that some of them are still there.
Using them means watching how price behaves when it reaches one of these levels.
Start with support, in a downtrend. When the price breaks below support and keeps falling, that is read as a sell signal: the downtrend has been confirmed. If instead the price touches support and bounces, the level has held. That is a reason to expect at least a pause in the decline; it is not, by itself, evidence that an uptrend is about to start. In a downtrend a bounce is often just a pullback before the next leg down.
Resistance works the same way in reverse. Picture an asset in an uptrend. When the price breaks above resistance and keeps rising, that is read as a buy signal: the uptrend has been confirmed. If the price touches resistance and turns back down, the level has held. One session's rejection is a warning that the advance may stall; calling it a trend reversal takes more than that, such as a lower high or a break of the last swing low.
A level is only worth having if the trader has decided in advance what a break and a bounce would mean for the position. And a stop loss belongs on the far side of the level, where the message would have changed, not a few pips inside it where ordinary noise can reach it; the article on where to place a stop loss in forex goes through that placement in detail.
What Makes Support and Resistance Dynamic
Static support and resistance are easy to identify: previous swing lows and highs on whatever timeframe the trader works on, daily for short-term trading, weekly or monthly for longer horizons. Lows serve as support, highs as resistance. The guide to drawing support and resistance levels covers how to pick those points.
The weakness of static levels is that they are fixed while the market is not: a high from three weeks ago says where sellers were then, and that information ages. The risk is that the levels go stale, or worse, give false signals. This is where dynamic support and resistance come in: levels that move with the market and update with every new bar.
The practical advantage is that once the tool is on the chart it does not have to be redrawn every session. A moving average or a band recalculates itself. The price of that convenience is that a dynamic level is a calculation rather than a place where buyers and sellers actually met, so it has to earn its credibility on the chart. Three common methods follow.
Method One: Moving Averages
The simplest method, because it relies on the most widely used indicator there is: the moving average. A moving average is a line whose points are the average price over a set number of previous bars. A simple average weights every bar equally; a weighted or exponential average gives more weight to recent bars.
A moving average is called slow when it covers many bars and fast when it covers few. There is no fixed boundary: "fast" and "slow" only mean shorter and longer than the other average on the chart, and the same 26-period average spans about two hours on a five-minute chart and more than a month on a daily one.
To get dynamic support and resistance levels from moving averages, put two averages on the chart, one longer than the other. Twenty and 50 periods are a common pair, 50 and 200 on daily charts. An average running below the price can act as dynamic support, one running above it as dynamic resistance; the further price sits from the average, the less often it reacts to it. When price crosses the average and holds on the other side, the average changes role, much as a broken horizontal level does.
Two cautions. A moving average has no memory of where buyers actually stepped in; it follows price, not the other way around, and in a sideways market it runs through the middle of the range and supports nothing. And a longer average lags: by the time the 200-day has turned, the move that turned it is largely done.
Method Two: Trendlines
A trendline is a straight line drawn through two or more swing lows (or swing highs); price touches it at those points and moves away in between. A line through swing highs acts as dynamic resistance, a line through swing lows as dynamic support. The line is dynamic because it slopes: the level it marks moves a little on every bar.
Trendlines are only as good as the points behind them. Two points define a line but prove nothing, since any two lows can be joined; a third touch is the first real evidence that the market respects it, and a line touched three or four times carries more weight than one drawn through two. A line that has to be redrawn after every session is not describing a trend, it is describing the wish for one.
Method Three: Bollinger Bands
Bollinger Bands consist of a moving average (20 periods by default) and two bands plotted two standard deviations of price above and below it. The bands widen when volatility rises and narrow when it falls, so their width is a reading of recent volatility rather than a fixed corridor.
In a range-bound market the lower band tends to act as dynamic support and the upper band as dynamic resistance, and a move from one band toward the other is the usual path. In a trending market it does not work that way: price can "walk" along a band for many bars. John Bollinger's own rules for the indicator say it directly: the bands give a relative definition of high and low, a touch of a band is not by itself a buy or sell signal, and in trends price can and does walk up the upper band and down the lower one.
The band method is the most systematic of the three, because it combines a moving average with a measured range, two standard deviations either side, rather than a line drawn by hand, and it is also the one most often misread. Before treating a band as support or resistance, ask whether the market is ranging or trending; the bands themselves help: narrow bands around a flat middle line suggest a range, expanding bands around a sloping one suggest a trend.
Putting the Three Together
No method is better in general; each describes a different aspect of the same chart. The moving average tracks the average price of recent bars, the trendline tracks the rhythm of the swings, the bands track volatility. The strongest dynamic levels are the places where two of them agree, for example a rising trendline that crosses the 50-period average at the same price.
That is also the logic behind the site's own tools. The support and resistance page lists up to three levels on each side of the price for every pair it covers, refreshed several times a day from the current analysis, and the high-probability zones page scores those levels by how many confluence factors line up on them. A dynamic level that coincides with one of those is worth more than either alone. The article on support and resistance: definition, purpose and calculation covers the calculation methods, and the piece on combining support, resistance and indicators shows how to confirm a level with an oscillator.
Whatever the method, the rule is the same as for a horizontal level: decide before the price gets there what a bounce and a break would mean, place the stop where the level would have failed, and treat every touch as information rather than as an instruction to trade.
