vs

Side-by-side financial comparison of BIODESIX INC (BDSX) and CASTLE BIOSCIENCES INC (CSTL). Click either name above to swap in a different company.

CASTLE BIOSCIENCES INC is the larger business by last-quarter revenue ($87.0M vs $28.8M, roughly 3.0× BIODESIX INC). On growth, BIODESIX INC posted the faster year-over-year revenue change (40.8% vs 0.8%). CASTLE BIOSCIENCES INC produced more free cash flow last quarter ($19.7M vs $692.0K). Over the past eight quarters, BIODESIX INC's revenue compounded faster (39.3% CAGR vs 9.2%).

Biodesix Inc is a molecular diagnostics enterprise specializing in developing and commercializing innovative blood-based testing solutions for oncology and infectious disease fields. It primarily serves healthcare providers, biopharmaceutical partners and patients across North America, with core business covering personalized medicine products that support clinical decision making.

Castle Biosciences Inc. is a commercial-stage diagnostic firm that develops and markets proprietary, clinically actionable tests for dermatological conditions such as melanoma and other skin cancers, plus rare diseases. It operates mainly in the U.S. healthcare market, focusing on segments with high unmet need for more accurate diagnostics to guide treatment choices.

BDSX vs CSTL — Head-to-Head

Bigger by revenue
CSTL
CSTL
3.0× larger
CSTL
$87.0M
$28.8M
BDSX
Growing faster (revenue YoY)
BDSX
BDSX
+39.9% gap
BDSX
40.8%
0.8%
CSTL
More free cash flow
CSTL
CSTL
$19.1M more FCF
CSTL
$19.7M
$692.0K
BDSX
Faster 2-yr revenue CAGR
BDSX
BDSX
Annualised
BDSX
39.3%
9.2%
CSTL

Income Statement — Q4 2025 vs Q4 2025

Metric
BDSX
BDSX
CSTL
CSTL
Revenue
$28.8M
$87.0M
Net Profit
$-4.0M
Gross Margin
79.0%
Operating Margin
-6.8%
-4.4%
Net Margin
-13.8%
Revenue YoY
40.8%
0.8%
Net Profit YoY
51.8%
EPS (diluted)
$-3.35
$-0.06

Green = leading value per metric. Periods may differ when fiscal calendars don't align.

8-Quarter Revenue & Profit Trend

Side-by-side quarterly history. Quarters aligned by calendar period so offset fiscal years line up.

Revenue
BDSX
BDSX
CSTL
CSTL
Q4 25
$28.8M
$87.0M
Q3 25
$21.8M
$83.0M
Q2 25
$20.0M
$86.2M
Q1 25
$18.0M
$88.0M
Q4 24
$20.4M
$86.3M
Q3 24
$18.2M
$85.8M
Q2 24
$17.9M
$87.0M
Q1 24
$14.8M
$73.0M
Net Profit
BDSX
BDSX
CSTL
CSTL
Q4 25
$-4.0M
Q3 25
$-8.7M
$-501.0K
Q2 25
$-11.5M
$4.5M
Q1 25
$-11.1M
$-25.8M
Q4 24
$-8.3M
Q3 24
$-10.3M
$2.3M
Q2 24
$-10.8M
$8.9M
Q1 24
$-13.6M
$-2.5M
Gross Margin
BDSX
BDSX
CSTL
CSTL
Q4 25
79.0%
Q3 25
77.5%
Q2 25
79.5%
Q1 25
81.4%
Q4 24
81.3%
Q3 24
81.8%
Q2 24
83.3%
Q1 24
81.0%
Operating Margin
BDSX
BDSX
CSTL
CSTL
Q4 25
-6.8%
-4.4%
Q3 25
-32.4%
-8.2%
Q2 25
-48.6%
-4.9%
Q1 25
-50.9%
-31.7%
Q4 24
-32.5%
4.7%
Q3 24
-47.3%
5.9%
Q2 24
-46.0%
5.8%
Q1 24
-74.4%
-7.5%
Net Margin
BDSX
BDSX
CSTL
CSTL
Q4 25
-13.8%
Q3 25
-40.0%
-0.6%
Q2 25
-57.3%
5.2%
Q1 25
-61.8%
-29.4%
Q4 24
-40.4%
Q3 24
-56.5%
2.6%
Q2 24
-60.3%
10.3%
Q1 24
-91.9%
-3.5%
EPS (diluted)
BDSX
BDSX
CSTL
CSTL
Q4 25
$-3.35
$-0.06
Q3 25
$-1.16
$-0.02
Q2 25
$-0.08
$0.15
Q1 25
$-0.08
$-0.90
Q4 24
$-5.02
$0.32
Q3 24
$-1.40
$0.08
Q2 24
$-0.08
$0.31
Q1 24
$-0.14
$-0.09

Balance Sheet & Financial Strength

Snapshot of each company's liquidity, leverage and book value from the latest quarter.

Metric
BDSX
BDSX
CSTL
CSTL
Cash + ST InvestmentsLiquidity on hand
$19.0M
$299.5M
Total DebtLower is stronger
$50.0M
$10.1M
Stockholders' EquityBook value
$-2.5M
$470.9M
Total Assets
$87.5M
$578.6M
Debt / EquityLower = less leverage
0.02×

8-quarter trend — quarters aligned by calendar period.

Cash + ST Investments
BDSX
BDSX
CSTL
CSTL
Q4 25
$19.0M
$299.5M
Q3 25
$16.6M
$287.5M
Q2 25
$20.7M
$275.9M
Q1 25
$17.6M
$275.2M
Q4 24
$26.2M
$293.1M
Q3 24
$31.4M
$95.0M
Q2 24
$42.2M
$85.6M
Q1 24
$11.5M
$82.9M
Total Debt
BDSX
BDSX
CSTL
CSTL
Q4 25
$50.0M
$10.1M
Q3 25
$50.0M
$10.0M
Q2 25
$50.0M
$10.0M
Q1 25
$40.0M
$10.0M
Q4 24
$40.0M
$10.0M
Q3 24
$40.0M
$10.0M
Q2 24
$40.1M
$10.0M
Q1 24
$40.1M
$10.0M
Stockholders' Equity
BDSX
BDSX
CSTL
CSTL
Q4 25
$-2.5M
$470.9M
Q3 25
$-1.7M
$467.0M
Q2 25
$1.1M
$455.4M
Q1 25
$11.1M
$440.3M
Q4 24
$20.9M
$455.8M
Q3 24
$27.9M
$441.1M
Q2 24
$36.3M
$423.9M
Q1 24
$-5.5M
$402.5M
Total Assets
BDSX
BDSX
CSTL
CSTL
Q4 25
$87.5M
$578.6M
Q3 25
$88.7M
$562.8M
Q2 25
$87.7M
$544.7M
Q1 25
$86.2M
$501.7M
Q4 24
$97.2M
$531.2M
Q3 24
$102.7M
$514.6M
Q2 24
$115.8M
$487.3M
Q1 24
$87.2M
$458.5M
Debt / Equity
BDSX
BDSX
CSTL
CSTL
Q4 25
0.02×
Q3 25
0.02×
Q2 25
43.95×
0.02×
Q1 25
3.62×
0.02×
Q4 24
1.92×
0.02×
Q3 24
1.44×
0.02×
Q2 24
1.10×
0.02×
Q1 24
0.02×

Cash Flow & Capital Efficiency

How much cash each business actually produces after reinvestment. Cash flow is harder to manipulate than net income.

Metric
BDSX
BDSX
CSTL
CSTL
Operating Cash FlowLast quarter
$778.0K
$26.9M
Free Cash FlowOCF − Capex
$692.0K
$19.7M
FCF MarginFCF / Revenue
2.4%
22.7%
Capex IntensityCapex / Revenue
0.3%
8.3%
Cash ConversionOCF / Net Profit
TTM Free Cash FlowTrailing 4 quarters
$-23.5M
$28.3M

8-quarter trend — quarters aligned by calendar period.

Operating Cash Flow
BDSX
BDSX
CSTL
CSTL
Q4 25
$778.0K
$26.9M
Q3 25
$-8.9M
$22.6M
Q2 25
$-6.6M
$20.8M
Q1 25
$-8.6M
$-6.0M
Q4 24
$-4.1M
$24.4M
Q3 24
$-10.7M
$23.3M
Q2 24
$-18.6M
$24.0M
Q1 24
$-15.3M
$-6.8M
Free Cash Flow
BDSX
BDSX
CSTL
CSTL
Q4 25
$692.0K
$19.7M
Q3 25
$-8.9M
$7.8M
Q2 25
$-6.6M
$11.6M
Q1 25
$-8.7M
$-10.8M
Q4 24
$-4.9M
$16.8M
Q3 24
$-10.9M
$17.0M
Q2 24
$-20.5M
$18.8M
Q1 24
$-15.5M
$-16.0M
FCF Margin
BDSX
BDSX
CSTL
CSTL
Q4 25
2.4%
22.7%
Q3 25
-41.0%
9.4%
Q2 25
-33.1%
13.4%
Q1 25
-48.3%
-12.2%
Q4 24
-24.2%
19.5%
Q3 24
-60.1%
19.8%
Q2 24
-114.3%
21.6%
Q1 24
-104.9%
-21.9%
Capex Intensity
BDSX
BDSX
CSTL
CSTL
Q4 25
0.3%
8.3%
Q3 25
0.2%
17.9%
Q2 25
0.3%
10.7%
Q1 25
0.4%
5.4%
Q4 24
4.1%
8.8%
Q3 24
1.3%
7.4%
Q2 24
10.7%
6.0%
Q1 24
1.6%
12.5%
Cash Conversion
BDSX
BDSX
CSTL
CSTL
Q4 25
Q3 25
Q2 25
4.60×
Q1 25
Q4 24
Q3 24
10.29×
Q2 24
2.69×
Q1 24

Financial Flow Comparison

Revenue → gross profit → operating profit → net profit for each company.

Revenue Breakdown by Segment

BDSX
BDSX

Diagnostic Tests$25.1M87%
Development Services$3.6M13%

CSTL
CSTL

Dermatologic$48.6M56%
Non Dermatologic$38.4M44%

Related Comparisons