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Quest DiagnosticsDGX -0.39%80 Market Cap is $22,896 Mil as of Jul. 21, 2026. GuruFocus rates DGX with a GF Score™ of 80/100 and a GF Value™ of $188.42 (Fairly Valued). The stock has 8 warning signs investors should review. Among 217 Medical Diagnostics & Research companies, Quest Diagnostics ranks better than 94.01% on this metric.
Market cap is the total market value to buy the whole company. It is equal to the share price times the number of Shares Outstanding (EOP). Quest Diagnostics's share price for the quarter that ended in Mar. 2026 was $195.98. Quest Diagnostics's Shares Outstanding (EOP) for the quarter that ended in Mar. 2026 was 111 Mil. Therefore, Quest Diagnostics's market cap for the quarter that ended in Mar. 2026 was $21,754 Mil.
Quest Diagnostics's quarterly market cap
declined
from Sep. 2025 ($21,121 Mil) to Dec. 2025 ($19,130 Mil) but then
increased
from Dec. 2025 ($19,130 Mil) to Mar. 2026 ($21,754 Mil).
Quest Diagnostics's annual market cap
increased
from Dec. 2023 ($15,365 Mil) to Dec. 2024 ($16,687 Mil) and
increased
from Dec. 2024 ($16,687 Mil) to Dec. 2025 ($19,130 Mil).
Enterprise Value is the theoretical takeover price. It is more comprehensive than market capitalization (market cap), which only includes common equity. Enterprise Value is calculated as the market cap plus debt and minority interest and preferred shares, minus total cash and cash equivalents. Quest Diagnostics's Enterprise Value for Today is $29,288 Mil.
Quest Diagnostics (NYSE:DGX) Market Cap Explanation
Market cap is not the real price you pay for a company. If you buy the company and become its owner, you become the owner of the cash the company has, and you also assume the companys debt. The real price you pay is the Enterprise Value.
Warren Buffett uses the ratio of total market cap of all public traded companies over GDP to measure if the market is expensive. As of April 2012, the US total market cap is about $14.7 trillion, while the US GDP is about $15 trillion. The market was modestly overvalued.
Quest Diagnostics Market Cap Related Terms
Quest Diagnostics Market Cap Historical Data
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The historical data trend for Quest Diagnostics's Market Cap can be seen below:
* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD. * For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.
For the Diagnostics & Research subindustry, Quest Diagnostics's Market Cap, along with its competitors' market caps and Market Cap data, can be viewed below:
* Competitive companies are chosen from companies within the same industry, with headquarter located in same country, with closest market capitalization; x-axis shows the market cap, and y-axis shows the term value; the bigger the dot, the larger the market cap. Note that "N/A" values will not show up in the chart.
Quest Diagnostics Market Cap vs Medical Diagnostics & Research Industry
For the Medical Diagnostics & Research industry and Healthcare sector, Quest Diagnostics's Market Cap distribution charts can be found below:
* The bar in red indicates where Quest Diagnostics's Market Cap falls into.
Market cap is the short version of market capitalization. It is the total market value to buy the whole company. It is equal to the share price times the number of shares outstanding.
Quest Diagnostics's Market Cap for the fiscal year that ended in Dec. 2025 is calculated as
* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD. * For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.
Quest Diagnostics (DGX) has a Market Cap of $22,896 Mil as of Jul. 21, 2026. Market cap equals the total value of a company's shares: price times shares outstanding. View historical data on Quest Diagnostics and its competitors. According to the industry distribution chart, Quest Diagnostics ranks #13 out of 217 companies in the Medical Diagnostics & Research industry, placing it in the top 6%.
Is Quest Diagnostics' Market Cap too high?
Quest Diagnostics' current Market Cap is $22,896 Mil. The Medical Diagnostics & Research industry median Market Cap is 56.47. Quest Diagnostics' value of $22,896 Mil is 40442.6% above this industry median. Based on the distribution chart, Quest Diagnostics ranks #13 out of 217 companies in the Medical Diagnostics & Research industry, which is in the top quartile — a strong position relative to peers. Overall, Quest Diagnostics has a GF Score™ of 80/100 and is considered Fairly Valued, reflecting its overall financial health beyond just this single metric.
How does Quest Diagnostics' Market Cap compare to LH and MTD?
According to the Medical Diagnostics & Research industry distribution chart, Quest Diagnostics ranks #13 out of 217 companies for Market Cap. This places Quest Diagnostics in the top 6% of its industry — outperforming the majority of peers. The industry median Market Cap is 56.47. Quest Diagnostics' value of $22,896 Mil is 40442.6% above this benchmark. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good Market Cap for a Medical Diagnostics & Research company?
The median Market Cap among Medical Diagnostics & Research companies is 56.47, based on 217 companies in the industry. Companies in the top quartile (top 25%) have a Market Cap significantly above this median, while those in the bottom quartile fall well below. However, Market Cap should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Quest Diagnostics's current Market Cap of $22,896 Mil is 40442.6% above the industry median. Use the industry distribution chart on this page to see where any company falls relative to its peers.
What does a high Market Cap mean?
A high Market Cap can signal that a stock is expensive relative to its fundamentals. Market cap equals the total value of a company's shares: price times shares outstanding. View historical data on Quest Diagnostics and its competitors. For the Medical Diagnostics & Research industry, the median Market Cap is 56.47 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Quest Diagnostics's current Market Cap is $22,896 Mil. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Quest Diagnostics stock overvalued right now?
Based on GuruFocus' analysis, Quest Diagnostics (DGX) is currently considered Fairly Valued. The stock's GF Value™ is $188.42, compared to a current price of $206.84 — trading 9.8% above its estimated fair value. The current Market Cap is $22,896 Mil and 40442.6% above the Medical Diagnostics & Research industry median of 56.47. Quest Diagnostics' overall GF Score™ is 80/100 with 8 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Market Cap calculated?
Market Cap is calculated from a company's financial statements. For Quest Diagnostics (DGX), the current Market Cap is $22,896 Mil as of Jul. 21, 2026. GuruFocus calculates this using data sourced from SEC filings and annual reports. See the calculation section and 30-year financial data on this page for the full breakdown.
Is Quest Diagnostics (DGX) Overvalued in 2026?
Based on GuruFocus' analysis, Quest Diagnostics stock appears to be overvalued.
The current stock price of $206.84 is trading 9.8% above its estimated GF Value™ of $188.42.
GuruFocus considers Quest Diagnostics to be Fairly Valued.
Key valuation signals for DGX:
Market Cap: $22,896 Mil
GF Value™: $188.42 vs. price of $206.84 (9.8% above fair value)
Industry Position: 40442.6% above the Medical Diagnostics & Research median (#13 of 217)
No single metric tells the full story. See the DGX stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Quest Diagnostics is a leading independent provider of diagnostic testing, information, and services in the US. The company generates over 97% of its revenue through clinical testing, anatomic pathology, esoteric testing, and substance abuse testing with specimens collected at its national network of roughly 2,400 patient service centers, as well as multiple doctors offices and hospitals. The firm also runs a much smaller diagnostic solutions segment that provides clinical trials testing, risk-assessment services, and information technology solutions.
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