Castle Biosciences, Inc. (CSTL) Key Metrics
CSTL valuation today
Trailing 12 months · as of October 18, 2026- Market cap
- $976.4M
- Enterprise value
- $836.0M
- P/E (TTM)
- —
- Forward P/E
- —
- PEG ratio
- —
- Price / sales
- 2.7 10-yr median 4.5
- Price / book
- 2.3 10-yr median 2.4
- EV / EBITDA
- 43.0 10-yr median 21.8
- Dividend yield
- —
- Beta
- 0.94
CSTL key metrics, 2017–2025
Fiscal year ended December 31, 2025 · U.S. dollarsCSTL valuation Price multiples at each fiscal year-end price.
Price / sales+39.5%
3.3
2025 · hover or tap a bar for each year
20172025
Price / book+40.0%
2.4
2025 · hover or tap a bar for each year
20172025
EV / EBITDA+467.1%
76.3
2025 · hover or tap a bar for each year
20172025
Price / free cash flow+86.6%
39.8
2025 · hover or tap a bar for each year
20172025
Free cash flow yield−2.2 pts
2.5%
2025 · hover or tap a bar for each year
20172025
CSTL returns How much profit the business earns on the capital it uses.
Return on equity−9.5 pts
−5.2%
2025 · hover or tap a bar for each year
20172025
Return on invested capital−21.2 pts
−17.0%
2025 · hover or tap a bar for each year
20172025
Return on assets−8.1 pts
−4.4%
2025 · hover or tap a bar for each year
20172025
Free cash flow margin−2.8 pts
8.2%
2025 · hover or tap a bar for each year
20172025
Asset turnover−8.0%
0.62
2025 · hover or tap a bar for each year
20172025
CSTL per-share figures Results divided by the shares outstanding at year-end.
Revenue per share+4.6%
$11.88
2025 · hover or tap a bar for each year
20172025
Earnings per share
−$0.83
2025 · hover or tap a bar for each year
20172025
Free cash flow per share−21.8%
$0.98
2025 · hover or tap a bar for each year
20172025
Book value per share+4.3%
$16.24
2025 · hover or tap a bar for each year
20172025
Shares outstanding−0.9%
29.0M
2025 · hover or tap a bar for each year
20172025
CSTL financial health Debt, liquidity and how easily interest is covered.
Debt / equity+35.6%
0.08
2025 · hover or tap a bar for each year
20172025
Net debt+$4.2M
−$262.6M
2025 · hover or tap a bar for each year
20172025
Net debt / EBITDA−16.15
−23.15
2025 · hover or tap a bar for each year
20172025
Current ratio−27.9%
5.26
2025 · hover or tap a bar for each year
20172025
Interest coverage
-497.8
2025 · hover or tap a bar for each year
20172025
Debt / assets+28.7%
0.06
2025 · hover or tap a bar for each year
20172025
CSTL efficiency & capital use Working capital cycle and where the cash goes.
Days sales outstanding+1 days
50 days
2025 · hover or tap a bar for each year
20172025
Days of inventory−1 days
47 days
2025 · hover or tap a bar for each year
20172025
Days payables outstanding+14 days
66 days
2025 · hover or tap a bar for each year
20172025
Cash conversion cycle−14 days
32 days
2025 · hover or tap a bar for each year
20172025
Capex / revenue+1.9 pts
10.5%
2025 · hover or tap a bar for each year
20172025
CSTL valuation history
Fiscal year-endToday9-year median
CSTL returns on capital
ROEROICROA
Net income (ROE, ROA) or after-tax operating income (ROIC) divided by the average of the opening and closing balance.
CSTL debt vs cash
Total debtCash & short-term investments
Debt includes short- and long-term borrowings and, where reported, lease liabilities.
CSTL cash returned to shareholders
DividendsBuybacksFree cash flow
CSTL price vs earnings per share
Share price at year-endEPS (right axis)
CSTL key metrics
2017–2025| 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | |
|---|---|---|---|---|---|---|---|---|---|
| Valuation | |||||||||
| Market capitalization | $1.13B | $779.6M | $578.4M | $613.3M | $1.08B | $1.27B | $297.6M | — | — |
| Enterprise value | $865.0M | $512.9M | $350.6M | $368.1M | $756.2M | $867.1M | $223.9M | — | — |
| P/E ratio | — | 42.7 | — | — | — | — | 56.4 | — | — |
| Price / sales | 3.3 | 2.3 | 2.6 | 4.5 | 11.5 | 20.3 | 5.7 | — | — |
| Price / book | 2.4 | 1.7 | 1.5 | 1.5 | 2.6 | 3.1 | 3.5 | — | — |
| Price / free cash flow | 39.8 | 21.3 | — | — | — | 248.5 | 49.0 | — | — |
| Price / operating cash flow | 17.5 | 12.0 | — | — | — | 128.8 | 42.4 | — | — |
| EV / sales | 2.5 | 1.5 | 1.6 | 2.7 | 8.0 | 13.8 | 4.3 | — | — |
| EV / EBITDA | 76.3 | 13.4 | — | — | — | — | 21.8 | — | — |
| EV / free cash flow | 30.5 | 14.0 | — | — | — | 169.5 | 36.8 | — | — |
| Earnings yield | −2.1% | 2.3% | −9.9% | −10.9% | −2.9% | −0.8% | 1.8% | — | — |
| Free cash flow yield | 2.5% | 4.7% | −3.3% | −7.7% | −2.1% | 0.4% | 2.0% | — | — |
| Dividend yield | — | — | — | 0.3% | 0.3% | — | — | — | — |
| Shareholder yield (dividends + buybacks) | — | — | 0.9% | 0.6% | 0.4% | — | 0.0% | — | — |
| Share price at fiscal year-end | $38.90 | $26.65 | $21.58 | $23.54 | $42.87 | $67.15 | $34.37 | — | — |
| Per share | |||||||||
| Revenue per share | $11.88 | $11.35 | $8.20 | $5.26 | $3.74 | $3.31 | $5.99 | $2.14 | $1.41 |
| Earnings per share | −$0.83 | $0.62 | −$2.14 | −$2.58 | −$1.24 | −$0.54 | $0.61 | −$0.60 | −$1.26 |
| Operating cash flow per share | $2.22 | $2.22 | −$0.21 | −$1.60 | −$0.76 | $0.52 | $0.81 | −$1.15 | −$1.25 |
| Free cash flow per share | $0.98 | $1.25 | −$0.72 | −$1.81 | −$0.89 | $0.27 | $0.70 | −$1.18 | −$1.30 |
| Cash per share | $10.33 | $10.02 | $9.07 | $9.93 | $13.11 | $21.65 | $11.42 | $0.42 | $0.12 |
| Book value per share | $16.24 | $15.58 | $14.60 | $15.32 | $16.38 | $21.96 | $9.83 | −$0.95 | −$1.46 |
| Tangible book value per share | $12.81 | $11.95 | $10.22 | $10.47 | $12.84 | $21.96 | $9.83 | −$0.95 | −$1.46 |
| Dividends per share | — | — | — | $0.06 | $0.12 | — | — | $0.00 | $0.00 |
| Capex per share | $1.24 | $0.97 | $0.51 | $0.22 | $0.14 | $0.25 | $0.11 | $0.03 | $0.05 |
| Debt per share | $1.27 | $0.90 | $0.57 | $0.51 | $0.33 | $0.31 | $2.90 | $2.30 | $1.90 |
| Shares outstanding | 29.0M | 29.3M | 26.8M | 26.1M | 25.1M | 18.9M | 8.7M | 10.7M | 9.8M |
| Change in shares outstanding | −0.9% | +9.2% | +2.9% | +3.6% | +32.8% | +118.6% | −18.7% | +8.9% | — |
| Returns & profitability | |||||||||
| Return on equity (ROE) | −5.2% | 4.3% | −14.5% | −16.6% | −7.6% | −4.1% | 14.1% | — | — |
| Return on invested capital (ROIC) | −17.0% | 4.2% | −33.8% | −47.1% | −62.1% | −44.8% | 67.7% | −46.4% | −276.0% |
| Return on assets (ROA) | −4.4% | 3.7% | −12.8% | −14.8% | −6.9% | −3.7% | 7.4% | −39.5% | −126.0% |
| Return on tangible assets | −5.0% | 4.3% | −17.1% | −20.9% | −8.4% | −2.3% | 4.4% | −28.4% | −126.5% |
| Free cash flow margin | 8.2% | 11.0% | −8.8% | −34.5% | −23.9% | 8.2% | 11.7% | −55.2% | −92.5% |
| Income quality (OCF / net income) | — | 3.56 | — | — | — | — | 1.33 | — | — |
| Financial health | |||||||||
| Total debt | $36.9M | $26.3M | $15.3M | $13.4M | $8.2M | $5.8M | $25.1M | $24.5M | $18.6M |
| Cash & short-term investments | $299.5M | $293.1M | $243.1M | $258.6M | $329.6M | $409.9M | $98.8M | $4.5M | $1.2M |
| Net debt | −$262.6M | −$266.8M | −$227.8M | −$245.2M | −$321.4M | −$404.0M | −$73.7M | $20.0M | $17.4M |
| Debt / equity | 0.08 | 0.06 | 0.04 | 0.03 | 0.02 | 0.01 | 0.30 | — | — |
| Debt / assets | 0.06 | 0.05 | 0.03 | 0.03 | 0.02 | 0.01 | 0.21 | 1.09 | 1.89 |
| Net debt / EBITDA | −23.15 | −7.00 | — | — | — | — | −7.17 | — | — |
| Current ratio | 5.26 | 7.29 | 6.20 | 8.09 | 14.21 | 20.58 | 7.63 | 2.69 | 1.28 |
| Quick ratio | 5.11 | 7.13 | 6.04 | 7.98 | 14.13 | 20.47 | 7.55 | 2.56 | 1.22 |
| Interest coverage | -497.8 | 15.0 | — | — | — | -2.5 | 1.6 | -1.7 | -6.6 |
| Working capital | $292.4M | $310.8M | $248.0M | $256.2M | $328.9M | $408.7M | $101.4M | $11.4M | $1.5M |
| Invested capital | $208.3M | $189.0M | $163.5M | $153.9M | $90.3M | $11.7M | $11.4M | $10.0M | $3.1M |
| Tangible asset value | $371.3M | $349.6M | $273.9M | $272.8M | $322.8M | $415.7M | $85.1M | −$10.1M | −$14.3M |
| Net current asset value | $253.4M | $284.8M | $233.6M | $244.1M | $302.9M | $406.0M | $82.0M | −$14.3M | −$17.4M |
| Graham number | — | $14.79 | — | — | — | — | $11.61 | — | — |
| Graham net-net per share | $7.92 | $8.89 | $7.97 | $8.83 | $11.65 | $20.97 | $8.76 | −$1.74 | −$1.97 |
| Capital allocation | |||||||||
| Dividends paid | — | — | — | $1.7M | $3.1M | — | — | $0 | $0 |
| Share buybacks (net) | — | — | $5.1M | $1.7M | $781,000 | — | $0 | $0 | $0 |
| Dividends + buybacks / free cash flow | — | — | — | — | — | — | 0.0% | — | — |
| Capex / revenue | 10.5% | 8.5% | 6.2% | 4.1% | 3.7% | 7.6% | 1.8% | 1.2% | 3.6% |
| Capex / operating cash flow | 56.0% | 43.7% | — | — | — | 48.2% | 13.4% | — | — |
| Capex / depreciation | 0.88 | 1.77 | 1.10 | 0.53 | 1.02 | 10.07 | 2.62 | 0.86 | 1.59 |
| Stock-based compensation / revenue | 13.3% | 15.2% | 23.3% | 26.5% | 23.1% | 13.3% | 2.4% | 1.3% | 0.8% |
| R&D / revenue | 15.1% | 15.7% | 24.4% | 32.8% | 31.5% | 21.2% | 14.2% | 21.3% | 32.5% |
| SG&A / revenue | 66.6% | 60.2% | 82.0% | 41.2% | 92.2% | 76.8% | 57.5% | 72.3% | 110.9% |
| Efficiency | |||||||||
| Days sales outstanding | 50.2 | 49.2 | 51.3 | 54.3 | 58.3 | 79.8 | 94.1 | 134.1 | 123.5 |
| Days of inventory on hand | 47.2 | 48.7 | 48.4 | 34.2 | 48.9 | 65.1 | 52.9 | 40.9 | 22.6 |
| Days payables outstanding | 65.8 | 52.0 | 60.9 | 41.5 | 53.6 | 74.7 | 82.8 | 88.5 | 82.8 |
| Cash conversion cycle (days) | 31.6 | 45.9 | 38.8 | 47.0 | 53.6 | 70.2 | 64.2 | 86.5 | 63.2 |
| Receivables turnover | 7.28 | 7.42 | 7.12 | 6.72 | 6.26 | 4.57 | 3.88 | 2.72 | 2.96 |
| Payables turnover | 5.55 | 7.01 | 6.00 | 8.80 | 6.81 | 4.89 | 4.41 | 4.13 | 4.41 |
| Inventory turnover | 7.73 | 7.49 | 7.55 | 10.67 | 7.47 | 5.61 | 6.90 | 8.93 | 16.16 |
| Asset turnover | 0.62 | 0.67 | 0.49 | 0.30 | 0.21 | 0.22 | 0.73 | 1.41 | 1.40 |
| Average receivables | $47.3M | $44.8M | $30.9M | $20.4M | $15.0M | $13.7M | $13.4M | $8.4M | $4.7M |
| Average payables | $12.8M | $8.6M | $7.5M | $3.6M | $2.3M | $2.0M | $1.7M | $1.3M | $1.1M |
| Average inventory | $9.2M | $8.0M | $6.0M | $3.0M | $2.1M | $1.7M | $1.1M | $593,404 | $304,576 |
| Intangibles / total assets | 17.2% | 20.0% | 25.9% | 28.2% | 19.2% | 0.0% | 0.0% | 0.0% | 0.4% |
Computed from CSTL's annual financial statements (latest annual report filed February 26, 2026) and the closing share price on each fiscal year-end, adjusted for stock splits. Figures in U.S. dollars; data from EODHD. Averages use the opening and closing balance of each year.
CSTL valuation and financial ratios
Castle Biosciences earned a return on equity of −5.2% and a return on invested capital of −17.0% in fiscal 2025. It ended the year with $36.9 million of debt and $299.5 million in cash and short-term investments, a net cash position of $262.6 million. The share count rose 196.3% from 9.8M to 29.0M over 8 years.
See the CSTL income statement, the CSTL chart for price history, or the CSTL stock overview for the latest quote and news.
CSTL key metrics FAQ
What is Castle Biosciences's EV/EBITDA?
Castle Biosciences's enterprise value was 76.3 times EBITDA at the end of fiscal 2025 (enterprise value $865.0 million, EBITDA $11.3 million); the current EV/EBITDA is 43.0.
What is Castle Biosciences's return on equity?
Castle Biosciences's return on equity (ROE) was −5.2% in fiscal 2025: net income of -$24.2 million on average shareholders' equity of $463.4 million.
What is Castle Biosciences's ROIC?
Castle Biosciences's return on invested capital was −17.0% in fiscal 2025, using after-tax operating income divided by average debt plus equity minus cash.
How much debt does Castle Biosciences have?
Castle Biosciences had total debt of $36.9 million at the end of fiscal 2025, a debt-to-equity ratio of 0.08 and more cash than debt.
What is Castle Biosciences's free cash flow yield?
Castle Biosciences generated $28.3 million of free cash flow in fiscal 2025, a free cash flow yield of 2.5% on its market value at year-end ($1.1 billion).
What is Castle Biosciences's current ratio?
Castle Biosciences's current ratio was 5.26 at the end of fiscal 2025: current assets were 5.26 times current liabilities.