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Castle BiosciencesCSTL -0.99%82 Intrinsic Value: Projected FCF is $8.75 as of Sep. 22, 2026. GuruFocus rates CSTL with a GF Score™ of 82/100 and a GF Value™ of $29.84 (Modestly Overvalued). The stock has 4 warning signs investors should review. Among 106 Medical Diagnostics & Research companies, Castle Biosciences ranks worse than 82.08% on this metric.
Since the intrinsic value calculations based on Discounted Cash Flow Intrinsic Value: DCF (FCF Based), or Discounted Earnings Intrinsic Value: DCF (Earnings Based) cannot be applied to companies without consistent revenue and earnings, GuruFocus developed a valuation model based on normalized Free Cash Flow and Book Value of the company. The details of how we calculate the intrinsic value of stocks are described in detail here.
As of today (2026-09-22), Castle Biosciences's Intrinsic Value: Projected FCF is $8.75. The stock price of Castle Biosciences is $34.99. Therefore, Castle Biosciences's Price-to-Intrinsic-Value-Projected-FCF of today is 4.0.
The historical rank and industry rank for Castle Biosciences's Intrinsic Value: Projected FCF or its related term are showing as below:
CSTL'
s Price-to-Projected-FCF Range Over the Past 10 Years
Min: 2.26 Med: 3.14 Max: 8.82
Current: 4
During the past 9 years, the highest Price-to-Intrinsic-Value-Projected-FCF of Castle Biosciences was 8.82. The lowest was 2.26. And the median was 3.14.
CSTL's Price-to-Projected-FCF is ranked worse than 82.08% of 106
companies
in the Medical Diagnostics & Research industry
Industry Median: 1.46
vs CSTL: 4.00
The growth multiple is capped between 8.35 and 17.74.
Total Stockholders Equity weighting is more art than science and it should always be revisited in more detail when researching a company. Weightings from 0% to 100% to more than 100% are possible. 80% was chosen as a happy median after taking the above ideas into consideration.
Castle Biosciences's Price-to-Intrinsic-Value-Projected-FCF for today is calculated as
Price-to-Intrinsic-Value-Projected-FCF
=
Share Price
/
Intrinsic Value: Projected FCF
=
34.99
/
9.8070552471091
=
3.57
* 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.
Castle Biosciences Intrinsic Value: Projected FCF Related Terms
Castle Biosciences Intrinsic Value: Projected FCF Historical Data
* Premium members only.
The historical data trend for Castle Biosciences's Intrinsic Value: Projected FCF 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.
CSTL vs OPK, FLGT, FRNM: Intrinsic Value: Projected FCF Comparison
For the Diagnostics & Research subindustry, Castle Biosciences's Price-to-Projected-FCF, along with its competitors' market caps and Price-to-Projected-FCF 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.
Castle Biosciences Price-to-Projected-FCF vs Medical Diagnostics & Research Industry
For the Medical Diagnostics & Research industry and Healthcare sector, Castle Biosciences's Price-to-Projected-FCF distribution charts can be found below:
* The bar in red indicates where Castle Biosciences's Price-to-Projected-FCF falls into.
Since the intrinsic value calculations based on Discounted Cash Flow Intrinsic Value: DCF (FCF Based), or Discounted Earnings Intrinsic Value: DCF (Earnings Based) cannot be applied to companies without consistent revenue and earnings, GuruFocus developed a valuation model based on normalized Free Cash Flow and Book Value of the company.
The details of how we calculate the intrinsic value of stocks are described in detail here.
This method smooths out the free cash flow over the past 6-7 years, multiplies the results by a growth multiple, and adds a portion of Total Stockholders Equity.
* 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.
What does a Intrinsic Value: Projected FCF of $8.75 mean?
Castle Biosciences (CSTL) has a Intrinsic Value: Projected FCF of $8.75 as of Sep. 22, 2026. Intrinsic Value: Projected FCF is the stock value based on a projected free cash flow model. View historical data on Castle Biosciences and its competitors. According to the industry distribution chart, Castle Biosciences ranks #87 out of 106 companies in the Medical Diagnostics & Research industry, placing it in the top 82.1%.
Is Castle Biosciences' Intrinsic Value: Projected FCF too high?
Castle Biosciences' current Intrinsic Value: Projected FCF is $8.75. The Medical Diagnostics & Research industry median Intrinsic Value: Projected FCF is 1.46. Castle Biosciences' value of $8.75 is 499.3% above this industry median. Based on the distribution chart, Castle Biosciences ranks #87 out of 106 companies in the Medical Diagnostics & Research industry, which is in the bottom quartile relative to peers. Overall, Castle Biosciences has a GF Score™ of 82/100 and is considered Modestly Overvalued, reflecting its overall financial health beyond just this single metric.
How does Castle Biosciences' Intrinsic Value: Projected FCF compare to OPK and FLGT?
According to the Medical Diagnostics & Research industry distribution chart, Castle Biosciences ranks #87 out of 106 companies for Intrinsic Value: Projected FCF. This places Castle Biosciences in the lower half of its industry. The industry median Intrinsic Value: Projected FCF is 1.46. Castle Biosciences' value of $8.75 is 499.3% 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 Intrinsic Value: Projected FCF for a Medical Diagnostics & Research company?
The median Intrinsic Value: Projected FCF among Medical Diagnostics & Research companies is 1.46, based on 106 companies in the industry. Companies in the top quartile (top 25%) have a Intrinsic Value: Projected FCF significantly above this median, while those in the bottom quartile fall well below. However, Intrinsic Value: Projected FCF should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Castle Biosciences's current Intrinsic Value: Projected FCF of $8.75 is 499.3% 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 Intrinsic Value: Projected FCF mean?
A high Intrinsic Value: Projected FCF can signal that a stock is expensive relative to its fundamentals. Intrinsic Value: Projected FCF is the stock value based on a projected free cash flow model. View historical data on Castle Biosciences and its competitors. For the Medical Diagnostics & Research industry, the median Intrinsic Value: Projected FCF is 1.46 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Castle Biosciences's current Intrinsic Value: Projected FCF is $8.75. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Castle Biosciences stock overvalued right now?
Based on GuruFocus' analysis, Castle Biosciences (CSTL) is currently considered Modestly Overvalued. The stock's GF Value™ is $29.84, compared to a current price of $34.99 — trading 17.3% above its estimated fair value. The current Intrinsic Value: Projected FCF is $8.75 and 499.3% above the Medical Diagnostics & Research industry median of 1.46. Castle Biosciences' overall GF Score™ is 82/100 with 4 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Intrinsic Value: Projected FCF calculated?
Intrinsic Value: Projected FCF is calculated from a company's financial statements. For Castle Biosciences (CSTL), the current Intrinsic Value: Projected FCF is $8.75 as of Sep. 22, 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 Castle Biosciences (CSTL) Overvalued in 2026?
Based on GuruFocus' analysis, Castle Biosciences stock appears to be overvalued.
The current stock price of $34.99 is trading 17.3% above its estimated GF Value™ of $29.84.
GuruFocus considers Castle Biosciences to be Modestly Overvalued.
Key valuation signals for CSTL:
Intrinsic Value: Projected FCF: $8.75
GF Value™: $29.84 vs. price of $34.99 (17.3% above fair value)
Industry Position: 499.3% above the Medical Diagnostics & Research median (#87 of 106)
No single metric tells the full story. See the CSTL stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Castle Biosciences Inc is a molecular diagnostics company. The group provides test solutions for the diagnosis and treatment of dermatologic cancers, Barrett's esophagus (BE), and uveal melanoma. The product portfolio of the company includes DecisionDx-Melanoma, a risk stratification gene expression profile (GEP) test; DecisionDx-SCC, a risk stratification test for cutaneous squamous cell carcinoma; MyPath Melanoma, a diagnostic GEP test for use in patients with difficult-to-diagnose melanocytic lesions; and TissueCypher, a test to predict future development of progression of high-grade dysplasia and/or esophageal cancer. The company derives revenues through the delivery of test reports for its molecular diagnostic tests.
82GF Score
Get the complete analysis for CSTL
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