# On-Balance Volume (OBV) {% embed url="" %} ​OBV (On Balance Volume) is an algorithm that mathematically measures the relationship between volume and price.
It was developed by Joseph Granville in **1960**. OBV relates price change and trading volume. When the closing price of the market is above the previous closing price, the trading volume is included in the transaction positively, while when the closing price of the market is below the previous closing price, the volume is included in the transaction negatively. * If today's closing price is greater than the previous day's closing price; **OBV = OBV of the previous day + Today's trading volume** * If today's closing price is less than the previous day's closing price; **OBV = OBV value of the previous day – Trading volume today** * If today's closing price is equal to the previous day's closing price; **OBV = OBV value of the previous day** OBV mostly moves in sync with price movements. As OBV increases, it is expected that the price will increase, and when it decreases, it is expected that the price will decrease, that is, the volume will move in the direction of supporting the price. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://academy.coinlegs.com/advances/on-balance-volume-obv.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.