The true strength index (TSI) is a technical indicator used in the analysis of financial markets that attempts to show both trend direction and overbought/oversold conditions.
[1][2] The indicator uses moving averages of the underlying momentum of a financial instrument.
The TSI combines these characteristics to create an indication of price and direction more in sync with market turns than either momentum or moving average.
[5] The TSI is provided as part of the standard collection of indicators offered by various trading platforms.
Blau suggests interpreting these values as overbought and oversold levels, respectively, at which point a trader may anticipate a market turn.