Money Flow Index (MFI): Definition, Calculations, and Pros & Cons


The Money flow index (MFI) is a versatile technical oscillator used in trading to identify overbought and oversold conditions, potential trend reversals, and divergences. This comprehensive guide explores the MFI in-depth, covering its significance, calculations, applications, and limitations. Discover how to effectively incorporate the MFI into your trading strategy to make informed decisions.

The money flow index (MFI): A deep dive into technical analysis

The Money flow index (MFI) is a powerful technical indicator that has become a vital tool for traders and investors seeking to navigate the complexities of the financial markets. In this comprehensive guide, we will take an in-depth look at the MFI, covering its significance, calculations, practical applications, and potential limitations. By the end of this article, you will have a thorough understanding of how to leverage the MFI to enhance your trading strategy.

Understanding the money flow index (MFI)

The Money flow index (MFI) is a technical oscillator that plays a pivotal role in the realm of technical analysis. It is designed to help traders make sense of market dynamics by providing insights into two critical aspects: overbought and oversold conditions and potential trend reversals. What sets the MFI apart from many other technical indicators is its unique utilization of both price and volume data.

Considered by some as the “volume-weighted RSI,” the MFI is a versatile tool that combines the best of both worlds. Unlike conventional oscillators like the Relative Strength Index (RSI), which rely solely on price data, the MFI incorporates volume information. This incorporation of volume data makes the MFI a valuable addition to a trader’s toolkit.

Key components of the MFI

Before we delve into its calculations and applications, let’s explore the key components that make up the money flow index:

  • Money flow ratio: The money flow ratio is a fundamental part of the MFI calculation. It measures the relationship between positive and negative money flows over a specified period. In essence, it tells us whether money is flowing into or out of an asset.
  • Raw money flow: Calculated by multiplying the typical price (more on this shortly) by the corresponding volume, the raw money flow helps us determine whether money flow is positive or negative for a particular period.
  • Typical price: To compute the typical price, we add together the high, low, and close prices for a given period and divide the result by three. This average price becomes the basis for calculating the raw money flow.

Now, let’s explore how these components come together to form the money flow index.

Calculating the money flow index (MFI)

Calculating the MFI involves several steps, each building on the previous one:

Compute the typical price for each of the last 14 periods. This involves adding together the high, low, and close prices for each period and dividing the result by three.

For each period, determine whether the typical price is higher or lower than the prior period. This simple comparison helps us identify positive and negative money flows.

Calculate the raw money flow by multiplying the typical price by the corresponding volume. If the typical price is higher than the previous period’s, the money flow is positive; otherwise, it’s negative.

Calculate the money flow ratio by summing up all the positive money flows over the last 14 periods and dividing it by the sum of the negative money flows over the same periods.

Finally, calculate the money flow index (MFI) using the money flow ratio obtained in the previous step. The formula is as follows:

Weigh the risks and benefits

Here is a list of the benefits and drawbacks of using the money flow index (MFI) in your trading strategy:

  • Provides insights into overbought and oversold conditions.
  • Identifies potential trend reversals through divergences.
  • Incorporates volume data for more accurate analysis.
  • Can be used across various timeframes and financial instruments.
  • May produce false signals leading to losing trades.
  • Not all price reversals are accompanied by divergences.
  • Should be used in conjunction with other analysis tools for better risk management.

As you can see, the MFI calculation is based on a series of logical steps, but it is often facilitated using spreadsheet software for convenience and accuracy. Each time a new period concludes, traders update the calculations based on the most recent 14 periods of data.

Interpreting the money flow index (MFI)

Now that you understand how the MFI is calculated, let’s explore how to interpret its readings and apply them in your trading strategy:


One of the primary ways to use the MFI is by identifying divergences between the MFI and price. When the MFI moves in the opposite direction of the price, it signals a potential reversal in the price trend. For example, if the MFI is declining while the price is rising, this suggests a forthcoming price reversal to the downside.

Overbought and oversold levels

The MFI provides clear overbought and oversold levels. Readings above 80 indicate overbought conditions, while readings below 20 indicate oversold conditions. These extremes can signal potential trading opportunities.

Larger divergences

Traders often watch for larger divergences using multiple waves in both price and MFI. For instance, if a stock makes successive highs while the MFI fails to confirm these highs, it can indicate an impending decline.

Additionally, the MFI’s overbought and oversold levels can serve as valuable signals. Movements below 10 and above 90 are relatively rare but can indicate potential long or short trade opportunities, respectively. Traders may also watch for moves back above 10 or below 90 to signal reversals.

The difference between the money flow index and the relative strength index (RSI)

It’s important to note that the MFI and RSI are closely related indicators. Both aim to provide insights into market conditions and potential reversals, but they differ in a fundamental way—the incorporation of volume data. The RSI focuses solely on price movements, while the MFI incorporates both price and volume information.

Proponents of volume analysis argue that it is a leading indicator, allowing the MFI to provide signals and warnings of possible reversals in a more timely fashion compared to the RSI. However, it’s crucial to understand that one indicator is not inherently better than the other. They simply serve different purposes and may provide signals at different times.

Limitations of the money flow index (MFI)

While the Money flow index is a valuable tool for traders, it has its limitations:

False signals

Like many technical indicators, the MFI can produce false signals. This occurs when the indicator suggests a favorable trading opportunity that does not materialize as expected. Traders should exercise caution and consider other factors when making trading decisions.

Incomplete warnings

While divergences between the MFI and price are noteworthy, not all price reversals are accompanied by such divergences. Traders should not solely rely on the MFI and should complement their analysis with other forms of technical and fundamental analysis.

Frequently asked questions

Is the money flow index (MFI) suitable for all types of assets?

Yes, the MFI can be applied to a wide range of financial instruments, including stocks, currencies, commodities, and cryptocurrencies. It is a versatile indicator that provides valuable insights into market conditions across various asset classes.

Are there alternative indicators that complement the money flow index?

Yes, traders often use a combination of technical indicators to enhance their analysis. Some common complementary indicators include moving averages, Bollinger Bands, and the Moving Average Convergence Divergence (MACD) indicator. These indicators can provide additional confirmation and context for MFI signals.

Can the money flow index (MFI) be used for long-term investment strategies?

While the MFI is frequently used for short to medium-term trading, it can also be applied to long-term investment strategies. Traders and investors may use longer timeframes and adjust the MFI parameters to suit their investment goals. However, it’s important to combine the MFI with fundamental analysis when making long-term investment decisions.

Key takeaways

  • The Money flow index (MFI) is a versatile technical oscillator that integrates both price and volume data for trading analysis.
  • MFI readings above 80 and below 20 indicate overbought and oversold conditions, respectively.
  • Divergences between the MFI and price can signal potential trend reversals.
  • Traders often use the MFI in conjunction with other analysis tools for comprehensive risk management.
  • While closely related to the RSI, the MFI’s incorporation of volume data sets it apart and may provide different signal timings.
View Article Sources
  1. What is MFI? – University of Chicago
  2. About MFI – Carnegie Mellon University
  3. The multidimensional fatigue inventory (MFI) psychometric qualities of an instrument to assess fatigue – National Center for Biotechnology Information
  4. MFI financing strategy – United States Agency for International Development