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True Strength Index (TSI)


The True Strength Index (TSI) is a technical analysis tool that is used to measure the magnitude of price changes to understand trends in the market. It combines moving averages with double smoothing to produce an indicator value that oscillates around zero. Specifically, positive values suggest bullish trends, while negative ones suggest bearish trends.


True Strength Index: /truː strɛŋθ ˈɪndɛks/ (TSI: /tiː ɛs aɪ/)

Key Takeaways

<html><body><ol><li>True Strength Index (TSI) is a momentum oscillator used by traders to measure the strength of a price trend. It takes into account both short term and long term price momentum to provide a balanced view of market conditions.</li><li>The TSI is calculated using moving averages of price changes, usually over 25 days for the high and 13 days for the low. A positive TSI indicates upward momentum, while a negative TSI indicates downward momentum.</li><li>Traders often use TSI in conjunction with other technical indicators for buy and sell signals. Overbought or oversold conditions can be identified when TSI crosses above or below specific threshold levels.</li></ol></body></html>


The True Strength Index (TSI) is important in business and finance as it is a technical momentum oscillator used to provide trade signals based on overbought/oversold levels, crossovers, and divergence. The indicator helps to identify new trends, determining whether they are bullish or bearish, and provides an objective measure of the direction and magnitude of a security’s price momentum. By comparing the current TSI value with previous values, investors can anticipate potential price reversals and avoid false market signals, creating a reliable trading strategy that can lead to a more accurate prediction of future price movements.


The True Strength Index (TSI) is a widely-used tool in the field of technical analysis developed to evaluate market trends alongside momentum. The primary purpose of TSI is to provide traders and investors with relevant indicators that will help determine conditions of overbought or oversold assets. TSI also plays a significant role in distinguishing price direction and providing potential signals for buying and selling.Designed to depict the strength of the market, TSI can be used to spot divergences between the movement of prices and momentum, which often presages a market turnaround. When utilized as a momentum oscillator, the TSI will allow investors to see the overall flow of money. Firmly understanding how the True Strength Index works, and how to interpret its signals, can help investors maximize returns and cut back on losses by identifying potential price reversals early.


1. Stock Market Trading: The True Strength Index (TSI) is commonly used by stock traders and financial analysts to evaluate the strength of price trends for a given stock, commodities, or indices. For example, a trader might use the TSI to determine optimal buying or selling points for Alphabet Inc.’s (Google’s parent company) shares. When the TSI indicates an upcoming bullish trend, the trader may decide to buy the shares; when it indicates a bearish trend, they may decide to sell.2. Forex Trading: Currency traders also use the TSI to evaluate the strength and direction of currency pair trends. For instance, a Forex trader might use the TSI to gauge the momentum of the EUR/USD currency pair. If the TSI shows a positive momentum, they might buy the pair expecting the euro to strengthen against the dollar. If it shows negative momentum, they might sell the pair expecting the euro to weaken against the dollar.3. Cryptocurrency Investment: TSI is also applicable in the world of cryptocurrency to determine the buying and selling points of various digital assets. For instance, if a crypto investor uses TSI to analyze the trend strength of Bitcoin, and TSI indicates a strong upward price trend, the investor may consider it an appropriate time to invest. Conversely, if the TSI displays a strong downward trend, it might suggest a good time to sell or hold off on buying more.

Frequently Asked Questions(FAQ)

What is the True Strength Index (TSI)?

The True Strength Index (TSI) is a momentum oscillator that helps traders identify new trends and confirm existing trends in the market. It measures both the magnitude and the direction of price changes.

How is the True Strength Index (TSI) calculated?

The TSI is calculated using a four-step process: Firstly, the price change is calculated. Secondly, the price change is smoothed. Then, the smoothed price changes are squared and averaged to form the final calculation basis. Lastly, a moving average of the squared smoothed price change is formed to create the final TSI number.

I am a trader, how should I use the True Strength Index (TSI)?

The TSI can help traders identify oversold or overbought conditions, bullish or bearish market trends, and generate buy or sell signals. When TSI crosses above zero, it may indicate a bullish signal, while crossing below zero may signal a bearish move.

What does a negative or positive TSI value imply?

A positive TSI value suggests upward momentum – the bulls are stronger than the bears. Conversely, a negative TSI value indicates that downward momentum is stronger – the bears have the upper hand.

How reliable is the True Strength Index (TSI) for market prediction?

While the TSI can prove quite helpful in predicting price trends, it is not infallible and should be used in conjunction with other technical indicators and market analysis tools for the most accurate predictions.

Is the True Strength Index (TSI) preferable for long-term or short-term trading?

The TSI can be used for both short-term and long-term trading. Short-term traders often use it to identify overbought or oversold conditions, while long-term investors may use it to confirm the existence of a stable trend. However, the decision greatly depends on individual strategies and investment goals.

How does the True Strength Index differ from other momentum oscillators?

The TSI is particularly beneficial as it less prone to false signals and ‘noise’ compared to other indicators. This is because it uses a double smoothing process, which can help filter out insignificant price movements.

Related Finance Terms

  • Momentum Indicators
  • Relative Strength Index (RSI)
  • Double Smoothed Exponential Moving Average
  • Trend Direction and Strength
  • Oversold and Overbought Conditions

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