ILMN vs TEM: How Illumina and Tempus AI Compare (2026)
Last updated August 2026
Short answer
ILMN is the larger of the two ($31.03B market cap): the incumbent the market prices for continued execution (34.57x forward earnings, beta 1.47). TEM is the smaller challenger ($7.92B), priced similarly on forward earnings (-907.72x): more room to run, but more to prove. The real question is which set of drivers you believe, and whether owning one (or both) leaves you over-concentrated.
ILMN vs TEM: the tie-breaker metrics
Same yardstick, side by side (as of August 2026). Valuation lined up like this is most meaningful for two names in the same corner of the market, which these are. Figures are approximate; verify before investing.
| Metric | ILMN | TEM | What it tells you |
|---|---|---|---|
| Market cap | $31.03B | $7.92B | Size. The larger name is the incumbent; the smaller has more room to grow and more to prove. |
| Forward P/E | 34.57 | -907.72 | Valuation on next year's expected earnings, the same yardstick for both. Lower is cheaper for that growth; higher means the market is paying up. |
| Beta | 1.47 | 3.46 | Volatility vs the market. Above 1 swings harder than the index; below 1 is steadier. Higher beta means bigger drawdowns to hold through. |
| Price vs 52-week range | 99% of range | 5% of range | Where today's price sits between the 52-week low and high. Near the high is momentum with less margin of safety; near the low is out of favor or a discount, depending on why. |
| Price / book | 11.65 | 18.89 | How much you pay over book value. Very high can signal an asset-light, high-return business or a rich price. |
Before you buy: how ILMN and TEM affect your concentration
The metrics above tell you which is the marginally better business. The bigger risk for most people is not picking the slightly worse stock, it is over-concentrating. ILMN and TEM share themes, so owning both, or adding either to what you already hold, can quietly push a large share of your portfolio into one bet.
This is the part a generic comparison page cannot answer, because it depends on what you own. Connect your brokerage and Walnut shows your real, combined ILMN and TEM exposure, flags overlap with your existing positions, and tells you if adding one would tip you past a concentration you are comfortable with, read-only by default, with your login staying at your broker. Walnut is not an investment adviser.
What does Illumina (ILMN) do?
Illumina designs, makes, and sells next-generation DNA sequencing systems and the consumables that run on them, serving research, clinical, and applied-genomics customers. Its business follows a razor-and-blades model: instruments such as the high-throughput NovaSeq X, the NextSeq, and the benchtop MiSeq seed an installed base, and the bulk of revenue then comes from recurring sequencing consumables (reagents and flow cells), which historically make up the majority of sales. The company is also pushing into multiomics, proteomics, and clinical diagnostics to expand what its platforms can measure. Illumina is headquartered in San Diego, was founded in 1998, and is led by CEO Jacob Thaysen.
What does Tempus AI (TEM) do?
Tempus AI (NASDAQ: TEM) is a Chicago-based technology company that applies artificial intelligence to precision medicine, primarily in oncology but increasingly across cardiology, neuropsychiatry, and hereditary conditions. It operates two interconnected business lines: a diagnostics segment that performs next-generation sequencing (NGS), PCR profiling, molecular pathology, and hereditary genetic tests through CAP-accredited, CLIA-certified laboratories, charging on a per-test basis; and a Data and Applications segment that licenses de-identified, linked clinical, molecular, and imaging datasets to life sciences companies (Insights), offers clinical trial matching (Trials), and deploys AI-powered algorithm products for physicians (Algos) and an AI platform called Next. Approximately 95% of the top 20 pharmaceutical companies use Tempus data or trial services, and the platform has integrations across more than 7,000 physicians and hundreds of research partners, creating a self-reinforcing network where clinical volume generates data that improves AI models and attracts more customers.
ILMN vs TEM: how do they differ?
Both fit overlapping themes, but they are not interchangeable. The useful comparison is which set of drivers and risks you want exposure to.
- ILMN drivers: Installed base and the consumables annuity; The NovaSeq X transition.
- TEM drivers: Explosive Revenue Growth with a Clear Path to Profitability; Data Licensing as a High-Margin Flywheel.
Which fits which kind of investor
A faster-growing, richer-valued name usually swings harder, so it suits a longer horizon and a higher tolerance for volatility; a steadier, more cash-generative business suits a more conservative or income-minded investor. The honest test is which set of risks you could hold through a drawdown: Competition is intensifying: Ultima Genomics markets bulk whole-genome sequencing near $80 a genome, Element Biosciences' AVITI undercuts benchtop economics, and PacBio and Oxford Nanopore hold long-read niches, all pressuring Illumina's pricing and share. For TEM, tempus remains unprofitable on a GAAP basis, with a full-year 2025 net loss of $245 million (which included $136 million in stock-based compensation), and the path to sustained GAAP profitability is long; Q1 2026 showed a net loss of $125.9 million, widening 85% year-over-year, and EPS missed analyst estimates by 34%.
ILMN or TEM: which should you pick?
Growth-minded investors who believe the theme has years to run tend to accept the richer multiple for more upside; value-minded investors lean toward the cheaper forward earnings and steadier profile. Pick ILMN if you believe its drivers more; TEM if you believe its. Many investors hold both, but since they share themes, that is a concentrated bet, not diversification. Decide deliberately and check overlap. For the full detail, see the ILMN and TEM guides.
ILMN vs TEM: the full fundamentals
ILMN. Illumina trades at a premium earnings multiple that reflects its platform dominance and consumables annuity, set against low-single-digit revenue growth and a slow-growing end market. Full-year 2025 revenue was about $4.34 billion, and the company guided fiscal 2026 to roughly $4.5 to $4.6 billion with operating margins recovering toward the low-to-mid 20s. All figures are approximate, tied to the June 2026 asOf date, and move with the share price and reported results; verify current numbers before relying on them.
TEM. Tempus trades at roughly 6.6 times trailing twelve-month revenue, a premium that reflects the market pricing in a future where its data-licensing flywheel generates high-margin recurring revenue at scale. The P/E ratio is not meaningful today because the company is not yet GAAP profitable, but consensus estimates suggest the first meaningful earnings could arrive by 2028, and the company's own guidance calls for positive Adjusted EBITDA of approximately $65 million in 2026. The gross margin of approximately 63% is already at software-like levels and has expanded significantly as the higher-margin Data and Applications segment grows faster than diagnostics.
Headline figures (approximate, June 2026): ILMN shows revenue (fy2025) ~$4.34 billion (approximate, verify), 2026 revenue guidance ~$4.5-4.6 billion, ~4-6% growth (company guidance, verify), consumables mix Majority of revenue is recurring consumables (razor-and-blades; verify), non-gaap operating margin (2026 guide) ~23.3-23.5% (company guidance, verify); TEM shows revenue (fy2025, reported) ~$1.27 billion, revenue (ttm, as of q1 2026) ~$1.36 billion, q1 2026 revenue (most recent quarter) ~$348 million (up 36% YoY), gross margin (fy2025) ~63%.
The bottom line: ILMN vs TEM
ILMN and TEM are related but distinct: same themes, different businesses and risks. Neither wins in the abstract; the right pick is whichever thesis you actually believe, sized so you are not over-concentrated in one theme. Walnut can show your combined ILMN and TEM exposure against your real portfolio. It is not an investment adviser.
Wondering how ILMN or TEM fits the portfolio you already own? Walnut is an AI investing app that connects your brokerage read-only and answers questions like that about your actual holdings: overlap, concentration, and how each position tracks the S&P 500. Compare the best AI portfolio analyzers or see the best AI investing apps in 2026.
Investing in Illumina with AI
Connect the broker you already use and ask Walnut's AI how ILMN fits what you actually hold: whether you own it already through a fund, what it would do to your concentration, and how it has tracked the S&P 500. Read-only by default, and you approve anything before it reaches your broker.
FAQ
What is the difference between ILMN and TEM?
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Illumina designs, makes, and sells next-generation DNA sequencing systems and the consumables that run on them, serving research, clinical, and applied-genomics customers. Tempus AI (NASDAQ: TEM) is a Chicago-based technology company that applies artificial intelligence to precision medicine, primarily in oncology but increasingly across cardiology, neuropsychiatry, and hereditary conditions. They show up together because they share investment themes, but they are different businesses, so the better fit depends on which thesis you are expressing.
Is ILMN or TEM the better stock?
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Neither is universally better. ILMN is the larger incumbent; TEM is the smaller challenger and looks cheaper on forward earnings. Walnut is informational, not investment advice. Compare what each does, the tie-breaker metrics above, and the risks, then decide which fits your thesis and what you already own.
Which is cheaper, ILMN or TEM?
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On forward P/E (as of August 2026), ILMN trades at 34.57x and TEM at -907.72x, so TEM is the cheaper of the two on next year's expected earnings. A lower multiple is not automatically the better buy: a richer valuation can be justified by faster growth, and a lower one can reflect real risk. Weigh the multiple against how fast each business is compounding.
Should you own both ILMN and TEM?
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Because they share themes, owning both concentrates you in that theme. That can be intentional (a focused bet) or accidental (less diversification than it looks). Walnut can show your combined exposure across both, and whether adding either over-concentrates you, before you buy.
What are the risks of ILMN vs TEM?
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ILMN: Competition is intensifying: Ultima Genomics markets bulk whole-genome sequencing near $80 a genome, Element Biosciences' AVITI undercuts benchtop economics, and PacBio and Oxford Nanopore hold long-read niches, all pressuring Illumina's pricing and share. The underlying sequencing market is growing slowly, and soft academic and research funding, including pressure on US research budgets, can delay instrument purchases. China is now only about 3% of revenue after Illumina was effectively shut out of that market, where domestic players BGI and MGI dominate. Tariffs and a relatively high valuation add further risk. TEM: Tempus remains unprofitable on a GAAP basis, with a full-year 2025 net loss of $245 million (which included $136 million in stock-based compensation), and the path to sustained GAAP profitability is long; Q1 2026 showed a net loss of $125.9 million, widening 85% year-over-year, and EPS missed analyst estimates by 34%. Reimbursement risk is material: a significant portion of Tempus's diagnostics revenue depends on favorable coverage decisions from CMS and private payers, and adverse rulings on NGS tests or laboratory-developed tests (LDTs) could reduce revenue per test sharply. Regulatory scrutiny of LDTs by the FDA, ongoing data privacy obligations under HIPAA, and the risk that competitors such as Guardant Health, Illumina, Roche, or PathAI develop comparable datasets or lower-priced tests could compress both volume growth and pricing power over time.
Walnut is informational, not investment advice. This page is descriptive and not a recommendation to buy or sell ILMN or TEM; figures are approximate and dated (as of August 2026). Verify current data before investing.