As of October 2026 Quest Diagnostics has a market cap of HK$200.05 Billion. This makes Quest Diagnostics the world's 950th most valuable company by market cap according to our data. The market capitalization, commonly called market cap, is the total market value of a publicly traded company's outstanding shares and is commonly used to measure how much a company is worth.
On Oct 8th, 2026 the market cap of Quest Diagnostics was reported to be: