There are many ratios that investors use to evaluate stocks, but some of the key ratios to consider are:

Price-to-Earnings (P/E) Ratio: This ratio measures a company's current stock price relative to its earnings per share (EPS). A lower P/E ratio indicates that the stock may be undervalued relative to its earnings, while a higher P/E ratio may suggest that the stock is overvalued.
Price-to-Sales (P/S) Ratio: This ratio compares the current stock price of a company to its revenue per share. This ratio can help in evaluating the companies that have negative earnings, but it should be used in conjunction with other ratios.
Price-to-Book (P/B) Ratio: This ratio compares a company's current stock price to its book value per share. it is the net value of a company's assets after liabilities are subtracted. A lower P/B ratio may suggest that a company is undervalued.
Debt-to-Equity Ratio: This ratio compares a company's total debt to its shareholder equity. A higher debt-to-equity ratio may indicate that a company has more debt relative to its equity, which could be a concern for investors.
Return on Equity (ROE): This ratio measures a company's net income as a percentage of shareholder equity. A higher ROE indicates that a company is generating more profits with the money invested by shareholders.
Dividend Yield: This ratio measures the dividend payment relative to the current stock price. Dividend yield is important for investors seeking income from their investments.

It's important to remember that no single ratio can provide a complete picture of a company's financial health. Investors should use multiple ratios and other factors, such as industry trends and management performance, to make informed investment decisions.

What are the key ratios to look at while buying stock?