How to Calculate Daily Stock Return

Find the closing share price of a stock for the current day and the previous day on a financial website, such as Yahoo! Finance, Google Finance or MSN Money. The prices can be found by entering the stock symbol in the 'Get Quotes,' or similarly named, box near the top of the financial website's homepage.
Subtract the previous day's closing price from the current day's close. If the stock increased in value, the number will be positive. A down day will result in a negative number. For example, assume your stock finished yesterday at $24.75 and today the price fell and finished at $22. Subtract $24.75 from $22 to get negative $2.75.
Divide the result by the previous day's close and multiply by 100 to convert to a percentage. Continuing the example, divide negative $2.75 by $24.75 for a result of negative 0.1111. Multiply by 100 to get a daily stock return of -11.11 percent.