The Relative Strength Index (RSI) is a momentum oscillator that measures the speed and change of price movements. The RSI is most typically used on a 14-day period, measured on a scale from 0 to 100. Traditionally, an asset is considered overbought or overvalued when the RSI is above 70 and oversold or undervalued when it is below 30. A shorter period RSI is more reactive to recent price changes, so it can show early signs of reversals. 9-Day RSI is sometimes used together with 14-Day RSI in a two period divergence strategy.
The Relative Strength Index (RSI), developed by J. Welles Wilder in his book “New Concepts in Technical Trading Systems.”, is a momentum oscillator that measures the speed and change of price movements. The RSI is most typically used on a 14-day period, measured on a scale from 0 to 100.
Traditionally, an asset is considered overbought or overvalued when the RSI is above 70 and oversold or undervalued when it is below 30. A RSI surpasses the 30 level indicates a bullish sign, when it slides below 70 level, it’s a bearish sign. This level can be adjusted depending on the security’s pattern and the market’s underlying trend. In an uptrend or bullish market, the RSI might range within a higher interval, investors could set the support level higher. If a downtrend or bearish market occurs, investors may need to lower the resistance level.
RSI can also be used in trading techniques to indicate the trading signal, such as Divergences and Swing Rejections. A shorter period RSI is more reactive to recent price changes, so it can show early signs of reversals. 9-Day RSI is sometimes used together with 14-Day RSI in a two period divergence strategy.
Castle Biosciences 9-Day RSI Related Terms
CSTL vs FLGT, MYGN, OPK: 9-Day RSI Comparison
For the Diagnostics & Research subindustry, Castle Biosciences's 9-Day RSI, along with its competitors' market caps and 9-Day RSI 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 9-Day RSI vs Medical Diagnostics & Research Industry
For the Medical Diagnostics & Research industry and Healthcare sector, Castle Biosciences's 9-Day RSI distribution charts can be found below:
* The bar in red indicates where Castle Biosciences's 9-Day RSI falls into.
* Note that the formula uses a positive value for the average loss.
* 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 (CSTL) has a 9-Day RSI of 75.65 as of Jul. 02, 2026. According to the industry distribution chart, Castle Biosciences ranks #185 out of 218 companies in the Medical Diagnostics & Research industry, placing it in the top 84.9%.
Is Castle Biosciences' 9-Day RSI too high?
Castle Biosciences' current 9-Day RSI is 75.65. The Medical Diagnostics & Research industry median 9-Day RSI is 50.19. Castle Biosciences' value of 75.65 is 50.7% above this industry median. Based on the distribution chart, Castle Biosciences ranks #185 out of 218 companies in the Medical Diagnostics & Research industry, which is in the bottom quartile relative to peers. Overall, Castle Biosciences has a GF Score™ of 73/100 and is considered Modestly Undervalued, reflecting its overall financial health beyond just this single metric.
How does Castle Biosciences' 9-Day RSI compare to FLGT and MYGN?
According to the Medical Diagnostics & Research industry distribution chart, Castle Biosciences ranks #185 out of 218 companies for 9-Day RSI. This places Castle Biosciences in the lower half of its industry. The industry median 9-Day RSI is 50.19. Castle Biosciences' value of 75.65 is 50.7% 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 9-Day RSI for a Medical Diagnostics & Research company?
The median 9-Day RSI among Medical Diagnostics & Research companies is 50.19, based on 218 companies in the industry. Companies in the top quartile (top 25%) have a 9-Day RSI significantly above this median, while those in the bottom quartile fall well below. However, 9-Day RSI should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Castle Biosciences's current 9-Day RSI of 75.65 is 50.7% 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 9-Day RSI mean?
A high 9-Day RSI can signal that a stock is expensive relative to its fundamentals. For the Medical Diagnostics & Research industry, the median 9-Day RSI is 50.19 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Castle Biosciences's current 9-Day RSI is 75.65. 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 $29.18, compared to a current price of $24.72 — trading 15.3% below its estimated fair value. The current 9-Day RSI is 75.65 and 50.7% above the Medical Diagnostics & Research industry median of 50.19. Castle Biosciences' overall GF Score™ is 73/100 with 4 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is 9-Day RSI calculated?
9-Day RSI is calculated from a company's financial statements. For Castle Biosciences (CSTL), the current 9-Day RSI is 75.65 as of Jul. 02, 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 $24.72 is trading 15.3% below its estimated GF Value™ of $29.18.
GuruFocus considers Castle Biosciences to be Modestly Undervalued.
Key valuation signals for CSTL:
9-Day RSI: 75.65
GF Value™: $29.18 vs. price of $24.72 (15.3% below fair value)
Industry Position: 50.7% above the Medical Diagnostics & Research median (#185 of 218)
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.
73GF Score
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