What is an OHLC Chart

OHLC, or open-high-low-close, charts are a type of bar chart that shows open, high, low, and closing prices. Unlike line charts, OHLC charts enable technical analysts to evaluate intraday volatility and see where prices opened and closed.


OHLC charts consist of a vertical line and two short horizontal lines extending to the left and right of the horizontal line. The horizontal line extending to the left represents the opening price for the period, while the horizontal line extending to the right represents the closing price for the period. The height of the vertical line represents the intraday range for the period, with the high being the period's high and the low being the period's low.

Periods where the security has risen are characterized by a horizontal line on the left that's lower than the horizontal line on the right. Often times, these lines are colored black. Periods where the security has fallen are characterized by a horizontal line on the left that's higher than the horizontal line on the right. These lines are typically colored red.

Interpreting OHLC Charts

There are several different techniques that technical analysts use to interpret OHLC charts:

  • Vertical Height - The vertical height of OHLC chart lines is indicative of the volatility during the period. If the line height is great, then traders know that there's a lot of volatility and indecision in the market.
  • Horizontal Line Position - The position of the left and right horizontal lines tell technical analysts where the security closed relative to its highs and lows. If the security rallied higher, but the close was much lower than the high, traders might assume that the rally may have fizzled toward the end of the period.
  • Line Colors - The color of a series of OHLC chart lines - either black or red - is indicative of a higher or lower trend and provides insights at a glance. While more analysis may be necessary before making a decision, this information may be helpful for making quick decisions before looking further into the details.

Example of an OHLC Chart

The following example shows an OHLC chart for the S&P 500 SPDR ETF (SPY).

Example of OHLC chart.

Technical analysts interpreting the chart may note the low volatility leading up to February, characterized by short vertical lines, and the high volatility in early February, characterized by long vertical lines. In contrast, a line chart would simply show a line moving lower without being able to see the extent of the volatility during the early-February periods.