Profit Factor

Profit factor is one of the simplest and most widely reported trading statistics. It divides the total of all winning trades by the total of all losing trades. A profit factor above 1 means the strategy made more than it lost; below 1 means it lost money overall. Trading platforms and backtesting tools show it prominently because it summarises win rate and payoff ratio in one number. Like any single statistic, it needs context: sample size, costs and the shape of the results all matter.

The formula#

Profit factor = Gross profit / Gross loss

Gross loss is taken as a positive number. Include commissions and fees in each trade's result.

Linking profit factor to win rate and payoff ratio#

Profit factor = (Win rate × Payoff ratio) / (1 - Win rate)

What is a good profit factor?#

These are rough guides. A high frequency strategy with thousands of trades and a profit factor of 1.2 can be excellent, while a profit factor of 4 over 15 trades proves little.

Sample size matters#

With few trades, one big winner can make profit factor look spectacular. Remove the single best trade and recalculate: if the profit factor collapses, the result depends on luck. A common rule of thumb is to want at least 100 trades, preferably across different market conditions, before trusting the figure. See Statistical Significance in Trading.

Limitations#

• No timing information: says nothing about drawdowns or how long losses lasted. See Maximum Drawdown.
• No risk scaling: a profit factor of 1.5 at huge position sizes can still ruin an account. See Risk of Ruin.
• Sensitive to outliers in both directions.
• Ignores capital used and time in the market.

Using profit factor well#

1. Include all costs in trade results. See Transaction Costs.
2. Compare in sample and out of sample profit factors; a large drop suggests overfitting. See In-Sample vs Out-of-Sample Testing.
3. Track it over rolling windows in your journal to spot decay. See Trading Journal.
4. Combine with drawdown, expectancy and Sharpe ratio. See Expectancy and Sharpe Ratio.

Profit factor by market condition#

A single overall profit factor can hide very different behaviour in different conditions. Split your trades by market regime, such as trending versus ranging, high versus low volatility, or by instrument and time of day, and compute the profit factor for each group. A strategy with an overall profit factor of 1.4 might show 2.0 in trending markets and 0.8 in ranges, which suggests a filter that avoids ranges. See Structural Breaks and Regime Changes.

Frequently asked questions#

What is profit factor in trading?#

Gross profit from winning trades divided by gross loss from losing trades; above 1 means the strategy made money overall.

What is a good profit factor?#

Generally 1.5 or higher from a large sample of trades after costs; very high values from few trades should be treated with caution.

How is profit factor related to win rate?#

Profit factor equals win rate times payoff ratio divided by the loss rate, so the same profit factor can come from many combinations.

Next, learn the measure of the worst loss in Maximum Drawdown.