Astera Labs vs. Nebius: Which Technology Stock Is a Better Buy in 2026?

Investors looking for exposure to the infrastructure powering artificial intelligence face a tough choice between Astera Labs (NASDAQ:ALAB) and Nebius (NASDAQ:NBIS) as both companies scale rapidly in 2026.

Astera Labs focuses on specialized connectivity hardware and software that helps data centers manage massive AI workloads efficiently. Nebius Group provides a full-stack AI cloud platform designed for developers and researchers. While one sells the specialized components for data movement, the other provides the environment where AI models are trained and deployed.

The case for Astera Labs

Astera Labs designs purpose-built connectivity solutions like PCIe and Ethernet for rack-scale AI infrastructure. It serves major hyperscalers and AI accelerator vendors among semiconductor stocks. Customer concentration adds a significant layer of risk to the business, as one end customer accounted for over 70% of revenue in 2025.

In FY 2025, revenue reached nearly $852.5 million, representing growth of approximately 115.1% compared to the previous year. The company reported a net income of close to $219.1 million. This resulted in a net margin of roughly 25.7% for the period, indicating the company is profitable on a net basis.

As of its December 2025 balance sheet, the debt-to-equity ratio is approximately 0.0x, meaning the company carries no total debt relative to its shareholder equity. The current ratio, which measures the ability to cover short-term obligations with current assets, is roughly 10.2x. Free cash flow, or the cash left after capital spending, was approximately $281.8 million. Note that stock-based compensation represented roughly 50.1% of operating cash flow, which inflates reported cash generation since SBC is a non-cash expense added back in the cash flow statement.

The case for Nebius

Nebius operates as an AI cloud company, building full-stack infrastructure for training and deploying machine learning models. It serves a wide range of clients including research institutes, healthcare start-ups, and national AI programs.

In FY 2025, revenue reached nearly $529.8 million, marking a significant increase of approximately 479% over the prior year. The company reported a net income from continuing operations of $29 million. This reflects a net margin of roughly 5.5% for the fiscal year, showing the company turned profitable during this expansion phase.

As of its December 2025 balance sheet, the debt-to-equity ratio is approximately 1.1x, which means total debt slightly exceeds shareholder equity. The current ratio is roughly 3.1x, providing a buffer for short-term liabilities. Free cash flow was a negative $3.7 billion as the company invested heavily in infrastructure. Note that stock-based compensation represented roughly 21.6% of operating cash flow, which inflates reported cash generation since SBC is a non-cash expense added back in the cash flow statement.

Risk profile comparison

Astera Labs faces significant revenue concentration, with three customers representing about 86% of total sales. A loss of any major partner or a shift toward proprietary internal solutions by hyperscalers could severely impact financial results. It also relies on a fabless model through TSMC, exposing it to geopolitical tensions and trade disputes in East Asia.

Nebius operates in a competitive cloud market against massive incumbents like Amazon and Microsoft. While it has shown rapid growth, it faces risks associated with its global footprint and a complex regulatory environment across multiple countries. Success depends on the continued adoption of its specialized AI cloud ecosystem over more established, diversified competitors.

Valuation comparison

Nebius Group trades at a lower Forward P/E, which measures price against future earnings estimates, while Astera Labs carries a lower P/S ratio.

Valuation metrics sourced from Financial Modeling Prep (FMP) and may differ from other data providers.

Which stock would I buy in 2026?

Both companies are on fire, growing at a pace that is almost hard to fathom, and both are deeply embedded in the AI infrastructure build-out. But I'd go with Nebius.

Astera Labs is doing impressive work. Its connectivity chips are critical components inside the data centers that power AI workloads, and revenue has nearly doubled year over year. The risk here is concentration: Astera's fortune is tightly tied to a handful of hyperscaler customers and one dominant hardware ecosystem.

I like that Nebius is playing a different game entirely. It provides AI cloud computing directly to the companies building and running AI models, and demand is so far outpacing supply that customers are competing for every GPU cluster it brings online. Nvidia has taken a significant stake in the company, which is about as strong an endorsement as the AI industry offers.

For a long-term investor comfortable with volatility, Nebius offers a bigger canvas and a more defensible position as the AI cloud market matures.

Sara Appino has positions in Amazon, Nvidia, and Taiwan Semiconductor Manufacturing. The Motley Fool has positions in and recommends Amazon, Microsoft, Nvidia, and Taiwan Semiconductor Manufacturing. The Motley Fool recommends Astera Labs. The Motley Fool has a disclosure policy.