Cerebras Systems vs. Rigetti Computing: Is an AI or Quantum Computing Stock the Better Buy in 2026?

The computing world is at a crossroads where current AI leaders meet the next generation of processors. Investors are now weighing whether Cerebras Systems (CBRS -2.35%) or Rigetti Computing (RGTI -1.70%) is the better buy today.CollapseCBRS & RGTI: Performance ComparisonKey Financial MetricsCBRS – Cerebras Systems$207.42–2.35% (-$4.99)RGTI – Rigetti Computing$16.24–1.70% (-$0.28)Market Cap$50B52wk Range$160.81 - $386.34Gross Margin39.00%P/E Ratio-94.06EPS (TTM)$-2.26Market Cap$5.5B52wk Range$12.53 - $58.15Gross Margin-3975.14%P/E Ratio-18.51EPS (TTM)$-0.89CBRS – Cerebras Systems$207.42–2.35% (-$4.99)Market Cap$50B52wk Range$160.81 - $386.34Gross Margin39.00%P/E Ratio-94.06EPS (TTM)$-2.26RGTI – Rigetti Computing$16.24–1.70% (-$0.28)Market Cap$5.5B52wk Range$12.53 - $58.15Gross Margin-3975.14%P/E Ratio-18.51EPS (TTM)$-0.89Cerebras focuses on massive chips designed to dominate AI training and inference tasks. Rigetti is building superconducting quantum computers that could eventually solve problems today's machines cannot touch. Comparing them requires weighing current revenue against long-term scientific potential.The case for Cerebras SystemsCerebras is carving out a unique niche among semiconductor stocks by focusing on the physical scale of its processors. Its Wafer-Scale Engine is the largest chip ever produced, designed specifically to accelerate the complex workloads required for medical research, energy modeling, and agentic AI.In FY 2025, revenue reached about $510 million, representing growth of approximately 76% over the previous year. This rapid expansion helped the company achieve a net income of close to $238 million, indicating a significant improvement from its prior loss-making periods.As of its December 2025 balance sheet, the debt-to-equity ratio was negative 0.5x, which means total liabilities exceed shareholder equity. The company maintains what is known as the current ratio of roughly 2.1x, a metric that measures the ability to cover short-term debts with current assets. Free cash flow was approximately negative $393 million, showing the cash used after accounting for necessary capital investments.The case for Rigetti ComputingRigetti develops superconducting quantum processors and provides access to its systems through its cloud-based platform. The company works with major partners like Amazon.com Inc (AMZN -1.96%) and Microsoft Corp (MSFT +0.14%) while also serving government agencies like NASA and the Department of Energy.In FY 2025, revenue reached roughly $7.1 million, which was a decrease of around 34% compared to the prior fiscal year. The company reported a net loss of approximately $216 million for the period as it continued to invest heavily in research and development.As of its December 2025 balance sheet, the debt-to-equity ratio was 0.0x, indicating the firm carries virtually no debt relative to its equity. The current ratio of nearly 37.4x suggests a very high level of liquidity to fund its ongoing technological roadmaps. Free cash flow was approximately negative $77.2 million, which is the cash a company generates after subtracting capital expenditures.Risk profile comparisonCerebras faces intense competition from established chip giants and must navigate the high costs associated with proprietary manufacturing processes. The business also deals with risks regarding its dependence on the continued rapid growth of the AI market to sustain its high valuation.Rigetti faces significant risks regarding its financial viability, given its history of operating losses and the high capital intensity of quantum hardware. It also faces a concentrated customer base and fierce competition from well-funded rivals like Alphabet Inc (GOOG -2.84%) and International Business Machines (IBM +2.05%) that are also racing to achieve quantum advantage.Valuation comparisonCerebras appears more reasonably valued on a Forward P/E basis, while Rigetti carries a much higher P/S ratio due to its early-stage revenue levels.MetricCerebras SystemsRigetti ComputingForward P/E222xn/aP/S ratio71.2x409xValuation metrics sourced from Financial Modeling Prep (FMP) and may differ from other data providers.Which stock would I buy in 2026?These are two exciting companies into two of the possibly most impactful tech sectors we may see in our lifetimes.Cerebras has a strong niche in the AI explosion and should see incredible growth in the coming years. Cerebras has transformative partnerships with OpenAI and Amazon's AWS. Much of Cerebras's projected growth relies on the AI inference market growing from $66 billion last year to $292 billion by 2029. That's a huge potential market. Based partly on projections like that, Wall Street analyst consensus figures indicate Cerebras producing about $888 million in sales in fiscal 2026, exploding to about $3 billion in 2027 and $7.5 billion in 2028. The same estimates indicate Cerebras will move to healthy profitability as soon as 2028. Rigetti, meanwhile, seems more speculative. After all, the business had just $7 million in revenue last year. The company recently received a potential award of up to $100 million over three years to accelerate superconducting quantum computing R&D and address key technical challenges in scaling and advancing its systems. The deal, in which the federal government would also take equity in the business, would allow Rigetti to tackle key scaling bottlenecks associated with multichip architectures more rapidly. It would also enable management to accelerate multiple generations of superconducting quantum processors and associated control electronics at Fab-1, its dedicated quantum device manufacturing facility.In short, it's a transformative deal too.The choice here, then, is between two rather speculative stocks. Rigetti is alluring, but at the moment its P/S ratio is astonishingly high, even considering revenue projections out through the decade, which aren't seen exceeding $100 million.That leaves Cerebras as the choice, given its existing business base and projections of rapid AI growth.