CSTL (Castle Biosciences) Change In Inventory: $-3.6 Mil (TTM As of Mar. 2026)

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CSTL Castle Biosciences Inc CSTL
77 GF Score
Price $24.00
GF Value $29.20
Valuation Modestly Undervalued
! 4 Warning Signs
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What is Castle Biosciences Change In Inventory?

Castle Biosciences CSTL +3.85% 77 Change In Inventory is $-3.6 Mil 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.

Castle Biosciences's change in inventory for the quarter that ended in Mar. 2026 was $-0.2 Mil. It means Castle Biosciences's inventory increased by $0.2 Mil from Dec. 2025 to Mar. 2026 .

Castle Biosciences's change in inventory for the fiscal year that ended in Dec. 2025 was $-2.1 Mil. It means Castle Biosciences's inventory increased by $2.1 Mil from Dec. 2024 to Dec. 2025 .

Castle Biosciences's Total Inventories for the quarter that ended in Mar. 2026 was $10.5 Mil.

Days Inventory indicates the number of days of goods in sales that a company has in the inventory. Castle Biosciences's Days Inventory for the quarter that ended in Mar. 2026 was 46.03.

Inventory Turnover measures how fast the company turns over its inventory within a year. Castle Biosciences's Inventory Turnover for the quarter that ended in Mar. 2026 was 1.98.

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. Castle Biosciences's Inventory-to-Revenue for the quarter that ended in Mar. 2026 was 0.12.

Castle Biosciences  (NAS:CSTL) Change In Inventory Explanation

1. Days Inventory indicates the number of days of goods in sales that a company has in the inventory.

Castle Biosciences's Days Inventory for the quarter that ended in is calculated as:

Days Inventory=Average Total Inventories/Cost of Goods Sold*Days in Period
=10.3575/20.533*365 / 4
=46.03

2. Inventory Turnover measures how fast the company turns over its inventory within a year.

Castle Biosciences's Inventory Turnover for the quarter that ended in Mar. 2026 is calculated as

Inventory Turnover=Cost of Goods Sold / Average Total Inventories
=20.533 / 10.3575
=1.98

3. 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.

Castle Biosciences's Inventory to Revenue for the quarter that ended in Mar. 2026 is calculated as

Inventory-to-Revenue=Average Total Inventories / Revenue
=10.3575 / 83.679
=0.12

* 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 Change In Inventory Related Terms

Castle Biosciences Change In Inventory Historical Data

* Premium members only.

The historical data trend for Castle Biosciences's Change In 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.

Castle Biosciences Change In Inventory Chart

Castle Biosciences Annual Data
Trend Dec17 Dec18 Dec19 Dec20 Dec21 Dec22 Dec23 Dec24 Dec25
Change In Inventory
Get a 7-Day Free Trial Premium Member Only 0.33 -1.68 -3.96 -0.19 -2.14

Castle Biosciences Quarterly Data
Jun21 Sep21 Dec21 Mar22 Jun22 Sep22 Dec22 Mar23 Jun23 Sep23 Dec23 Mar24 Jun24 Sep24 Dec24 Mar25 Jun25 Sep25 Dec25 Mar26
Change In Inventory Get a 7-Day Free Trial Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only 1.29 -1.52 -0.31 -1.60 -0.21
CSTL
77GF Score
Castle Biosciences Inc CSTL
Change In Inventory is just one metric. See GF Score™, valuation, warning signs, and more.
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Castle Biosciences Change In Inventory Calculation

Change In Inventory is the difference between last period's ending inventory and the current period's ending inventory.

Change In Inventory for the trailing twelve months (TTM) ended in Mar. 2026 adds up the quarterly data reported by the company within the most recent 12 months, which was $-3.6 Mil.

* 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.

Frequently Asked Questions Learn more about Change In Inventory →
What does a Change In Inventory of $-3.6 Mil mean?
Castle Biosciences (CSTL) has a Change In Inventory of $-3.6 Mil as of Mar. 2026. Change in Inventory is the difference between current-period inventory and past-period inventory. View historical data for Castle Biosciences and its competitors.
Is Castle Biosciences' Change In Inventory too high?
Castle Biosciences' current Change In Inventory is $-3.6 Mil. 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' Change In Inventory compare to FLGT and MYGN?
Castle Biosciences' Change In Inventory of $-3.6 Mil can be compared against companies in the Medical Diagnostics & Research industry. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good Change In Inventory for a Medical Diagnostics & Research company?
A good Change In Inventory depends on the Medical Diagnostics & Research industry context. However, Change In Inventory 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 Change In Inventory mean?
A high Change In Inventory can signal that a stock is expensive relative to its fundamentals. Change in Inventory is the difference between current-period inventory and past-period inventory. View historical data for Castle Biosciences and its competitors. Castle Biosciences's current Change In Inventory is $-3.6 Mil. 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 $24.00 — trading 17.8% below its estimated fair value. The current Change In Inventory is $-3.6 Mil. 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 Change In Inventory calculated?
Change In Inventory is calculated from a company's financial statements. For Castle Biosciences (CSTL), the current Change In Inventory is $-3.6 Mil 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 $24.00 is trading 17.8% below its estimated GF Value™ of $29.20. GuruFocus considers Castle Biosciences to be Modestly Undervalued.

Key valuation signals for CSTL:

  • Change In Inventory: $-3.6 Mil
  • GF Value™: $29.20 vs. price of $24.00 (17.8% below fair value)
  • GF Score™: 77/100 with 4 warning signs

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 Business Description

Other Exchanges 086:Germany
Address 1500 West Parkwood Avenue, Suite 401, Friendswood, TX, USA, 77546
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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Change In Inventory is just one metric. See GF Value™, 30-year financials, guru trades, warning signs, and more.

$24.00
Price
$29.20
GF Value