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Quest DiagnosticsMIL:1QDX 54 Days Inventory is 9.62 as of Mar. 2026, which is 3% below its 10-year median of 9.88. GuruFocus rates MIL:1QDX with a GF Score™ of 54/100 and a GF Value™ of €163.64 (Fairly Valued). The stock has 8 warning signs investors should review. Among 179 Medical Diagnostics & Research companies, Quest Diagnostics ranks better than 93.85% on this metric.
The historical rank and industry rank for Quest Diagnostics's Days Inventory or its related term are showing as below:
MIL:1QDX'
s Days Inventory Range Over the Past 10 Years
Min: 6.56 Med: 9.88 Max: 11.96
Current: 9.46
During the past 13 years, Quest Diagnostics's highest Days Inventory was 11.96. The lowest was 6.56. And the median was 9.88.
MIL:1QDX's Days Inventory is ranked better than 93.85% of 179
companies
in the Medical Diagnostics & Research industry
Industry Median: 65.04
vs MIL:1QDX: 9.46
Quest Diagnostics's Days Inventory
declined
from Mar. 2025 (9.77) to Mar. 2026 (9.62).
Inventory Turnover measures how fast the company turns over its inventory within a year.
Quest Diagnostics's Inventory Turnover for the
three
months ended in Mar. 2026 was 9.49.
Inventory-to-Revenue determines the ability of a company to manage their inventory levels. It measures the percentage of Inventories the company currently has on hand to support the current amount of Revenue.
Quest Diagnostics's Inventory-to-Revenue for the
three
months ended in Mar. 2026 was 0.07.
Quest Diagnostics (MIL:1QDX) Days Inventory Explanation
Days Inventory indicates the liquidity of the inventory. Generally, a lower Days Inventory is preferred as it indicates a shorter duration to clear off the inventory. An increase of the ratio may indicate the company's sales slowed. Similar ratios related to Days Inventory are:
1. Inventory Turnover measures how fast the company turns over its inventory within a year.
Quest Diagnostics's Inventory Turnover for the
three
months ended in Mar. 2026 is calculated as
2. Inventory-to-Revenue determines the ability of a company to manage their inventory levels. It measures the percentage of Inventories the company currently has on hand to support the current amount of Revenue.
Quest Diagnostics's Inventory to Revenue for the
three
months ended in Mar. 2026 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.
Be Aware
A lot of business are seasonable. It makes more sense to compare Days Inventory from the same period in the previous year instead of from the previous quarter.
Quest Diagnostics Days Inventory Related Terms
Quest Diagnostics Days Inventory Historical Data
* Premium members only.
The historical data trend for Quest Diagnostics's Days Inventory 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.
MIL:1QDX vs LH, MTD, GH: Days Inventory Comparison
For the Diagnostics & Research subindustry, Quest Diagnostics's Days Inventory, along with its competitors' market caps and Days Inventory 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 Days Inventory vs Medical Diagnostics & Research Industry
For the Medical Diagnostics & Research industry and Healthcare sector, Quest Diagnostics's Days Inventory distribution charts can be found below:
* The bar in red indicates where Quest Diagnostics's Days Inventory falls into.
* 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 (MIL:1QDX) has a Days Inventory of 9.62 as of Mar. 2026. Days inventory represents the average amount of days a company holds inventory before selling it. View historical data on Quest Diagnostics and its competitors. This is near median its historical median of 9.88. Over the past decade, Quest Diagnostics' Days Inventory has ranged from 6.56 to 11.96. According to the industry distribution chart, Quest Diagnostics ranks #11 out of 179 companies in the Medical Diagnostics & Research industry, placing it in the top 6.1%.
Is Quest Diagnostics' Days Inventory too high?
Quest Diagnostics' current Days Inventory of 9.62 is near median its 10-year median of 9.88. Over the past 10 years, this metric has ranged from a low of 6.56 to a high of 11.96. The Medical Diagnostics & Research industry median Days Inventory is 65.04. Quest Diagnostics' value of 9.62 is 85.2% below this industry median. Based on the distribution chart, Quest Diagnostics ranks #11 out of 179 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 54/100 and is considered Fairly Valued, reflecting its overall financial health beyond just this single metric.
How does Quest Diagnostics' Days Inventory compare to LH and MTD?
According to the Medical Diagnostics & Research industry distribution chart, Quest Diagnostics ranks #11 out of 179 companies for Days Inventory. This places Quest Diagnostics in the top 6% of its industry — outperforming the majority of peers. The industry median Days Inventory is 65.04. Quest Diagnostics' value of 9.62 is 85.2% below this benchmark. Historically, Quest Diagnostics' own Days Inventory has ranged from 6.56 to 11.96 over the past decade. While the company's 10-year median is 9.88 vs. the industry median of 65.04, Quest Diagnostics has consistently been below the industry average. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good Days Inventory for a Medical Diagnostics & Research company?
The median Days Inventory among Medical Diagnostics & Research companies is 65.04, based on 179 companies in the industry. Companies in the top quartile (top 25%) have a Days Inventory significantly above this median, while those in the bottom quartile fall well below. However, Days Inventory should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Quest Diagnostics's current Days Inventory of 9.62 is 85.2% below 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 Days Inventory mean?
A high Days Inventory can signal that a stock is expensive relative to its fundamentals. Days inventory represents the average amount of days a company holds inventory before selling it. View historical data on Quest Diagnostics and its competitors. For the Medical Diagnostics & Research industry, the median Days Inventory is 65.04 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Quest Diagnostics's current Days Inventory is 9.62, which is near median its own 10-year median of 9.88. 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 (MIL:1QDX) is currently considered Fairly Valued. The stock's GF Value™ is €163.64, compared to a current price of €180.35 — trading 10.2% above its estimated fair value. The current Days Inventory is 9.62, which is near median its 10-year median of 9.88 and 85.2% below the Medical Diagnostics & Research industry median of 65.04. Quest Diagnostics' overall GF Score™ is 54/100 with 8 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Days Inventory calculated?
Days Inventory is calculated from a company's financial statements. For Quest Diagnostics (MIL:1QDX), the current Days Inventory is 9.62 as of Mar. 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 (MIL:1QDX) Overvalued in 2026?
Based on GuruFocus' analysis, Quest Diagnostics stock appears to be overvalued.
The current stock price of €180.35 is trading 10.2% above its estimated GF Value™ of €163.64.
GuruFocus considers Quest Diagnostics to be Fairly Valued.
Key valuation signals for MIL:1QDX:
Days Inventory: 9.62 (near median its 10-year median of 9.88)
GF Value™: €163.64 vs. price of €180.35 (10.2% above fair value)
Industry Position: 85.2% below the Medical Diagnostics & Research median (#11 of 179)
No single metric tells the full story. See the MIL:1QDX 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.
54GF Score
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