Boom I don't know of an indicator call resistance/ support. As I understand it, these levels are normally update daily without any indication of the strength. Meaning a resistance point established during a high volume day would become harder to break through then on a week volume day.
Every time a stock hits a new high and retraces the high becomes the resistance point. The point which new stock holder want to reach before selling. The same hold for the support side. Most websites which report these levels, as over lays on charts, will show several up and down. Think of them as layers of new stock holders.
Below are 2 links to websites which show these levels, stockta site shows confluence (a seperate indicator)beside the resistance/support, which is very powerful as it combines multiple technical analysis techniques to arrive at the same conclusion, and should be used as a strength indicator. Both are updated evenings after close of day.
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