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Castle BiosciencesCSTL -0.29%77 Debt-to-EBITDA is -0.89 as of Mar. 2026. GuruFocus rates CSTL with a GF Score™ of 77/100 and a GF Value™ of $29.20 (Modestly Undervalued). The stock has 4 warning signs investors should review. Among 112 Medical Diagnostics & Research companies, Castle Biosciences ranks worse than 892856.25% on this metric.
Debt-to-EBITDA measures a company's ability to pay off its debt.
A high Debt-to-EBITDA ratio generally means that a company may spend more time to paying off its debt. According to Joel Tillinghast's BIG MONEY THINKS SMALL: Biases, Blind Spots, and Smarter Investing, a ratio of Debt-to-EBITDA exceeding four is usually considered scary unless tangible assets cover the debt.
The historical rank and industry rank for Castle Biosciences's Debt-to-EBITDA or its related term are showing as below:
CSTL'
s Debt-to-EBITDA Range Over the Past 10 Years
Min: -14.59 Med: -0.23 Max: 3.25
Current: -14.59
During the past 9 years, the highest Debt-to-EBITDA Ratio of Castle Biosciences was 3.25. The lowest was -14.59. And the median was -0.23.
CSTL's Debt-to-EBITDA is ranked worse than 100% of 112
companies
in the Medical Diagnostics & Research industry
Industry Median: 2.29
vs CSTL: -14.59
A high Debt-to-EBITDA ratio generally means that a company may spend more time to paying off its debt.
According to Joel Tillinghast's BIG MONEY THINKS SMALL: Biases, Blind Spots, and Smarter Investing, a ratio of Debt-to-EBITDA exceeding four is usually considered scary unless tangible assets cover the debt.
Castle Biosciences Debt-to-EBITDA Related Terms
Castle Biosciences Debt-to-EBITDA Historical Data
* Premium members only.
The historical data trend for Castle Biosciences's Debt-to-EBITDA 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 FLGT, MYGN, OPK: Debt-to-EBITDA Comparison
For the Diagnostics & Research subindustry, Castle Biosciences's Debt-to-EBITDA, along with its competitors' market caps and Debt-to-EBITDA 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 Debt-to-EBITDA vs Medical Diagnostics & Research Industry
For the Medical Diagnostics & Research industry and Healthcare sector, Castle Biosciences's Debt-to-EBITDA distribution charts can be found below:
* The bar in red indicates where Castle Biosciences's Debt-to-EBITDA 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.
In the calculation of annual Debt-to-EBITDA, the EBITDA of the last fiscal year is used. In calculating the annualized quarterly data,
the EBITDA data used here is four times the quarterly (Mar. 2026) EBITDA data.
Castle Biosciences (CSTL) has a Debt-to-EBITDA of -0.89 as of Mar. 2026. Debt-to-EBITDA ratio represents the ratio of total debt to total earnings before interest, taxes, depreciation and amortization. View historical data on Castle Biosciences. According to the industry distribution chart, Castle Biosciences ranks #999999 out of 112 companies in the Medical Diagnostics & Research industry.
Is Castle Biosciences' Debt-to-EBITDA too high?
Castle Biosciences' current Debt-to-EBITDA is -0.89. Based on the distribution chart, Castle Biosciences ranks #999999 out of 112 companies in the Medical Diagnostics & Research industry, which is in the bottom quartile relative to peers. Overall, Castle Biosciences has a GF Score™ of 77/100 and is considered Modestly Undervalued, reflecting its overall financial health beyond just this single metric.
How does Castle Biosciences' Debt-to-EBITDA compare to FLGT and MYGN?
According to the Medical Diagnostics & Research industry distribution chart, Castle Biosciences ranks #999999 out of 112 companies for Debt-to-EBITDA. This places Castle Biosciences in the lower half of its industry. The industry median Debt-to-EBITDA is 2.29. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good Debt-to-EBITDA for a Medical Diagnostics & Research company?
The median Debt-to-EBITDA among Medical Diagnostics & Research companies is 2.29, based on 112 companies in the industry. Companies in the top quartile (top 25%) have a Debt-to-EBITDA significantly above this median, while those in the bottom quartile fall well below. However, Debt-to-EBITDA should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Use the industry distribution chart on this page to see where any company falls relative to its peers.
What does a high Debt-to-EBITDA mean?
A high Debt-to-EBITDA can signal that a stock is expensive relative to its fundamentals. Debt-to-EBITDA ratio represents the ratio of total debt to total earnings before interest, taxes, depreciation and amortization. View historical data on Castle Biosciences. For the Medical Diagnostics & Research industry, the median Debt-to-EBITDA is 2.29 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Castle Biosciences's current Debt-to-EBITDA is -0.89. 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 Undervalued. The stock's GF Value™ is $29.20, compared to a current price of $24.16 — trading 17.3% below its estimated fair value. The current Debt-to-EBITDA is -0.89. Castle Biosciences' overall GF Score™ is 77/100 with 4 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Debt-to-EBITDA calculated?
Debt-to-EBITDA is calculated from a company's financial statements. For Castle Biosciences (CSTL), the current Debt-to-EBITDA is -0.89 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 Castle Biosciences (CSTL) Overvalued in 2026?
Based on GuruFocus' analysis, Castle Biosciences stock appears to be undervalued.
The current stock price of $24.16 is trading 17.3% below its estimated GF Value™ of $29.20.
GuruFocus considers Castle Biosciences to be Modestly Undervalued.
Key valuation signals for CSTL:
Debt-to-EBITDA: -0.89
GF Value™: $29.20 vs. price of $24.16 (17.3% below fair value)
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.
77GF Score
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