Today’s computers are absolute beasts — able to chug through the billions of calculations needed for things like AI and cryptography. But what if we’re just scratching the surface? Quantum computing, which leverages the weird and wonderful properties of quantum physics, could eventually make today’s supercomputers look like abacuses. And while it’s still in its infancy, the quantum computing market is projected to grow at a whopping 32.7% annually (CAGR). For investors eager to get in on the ground floor of this growth, this guide will cover the top quantum computing stocks, ranked by pure-play focus.

Quantum computing has gained headlines for being “millions” or even “billions” of times faster than even our best modern computers. But that’s not quite the full story. In reality, quantum computers (at least in the near-term), will be better for certain types of problems — namely, highly complex ones with vast computational spaces. They will not be generalized “faster computers” capable of replacing current ones.

That means the main growth driver of the quantum computing market will be its transformative power across specific industries. In drug discovery, quantum computers could help identify new life-saving medications by simulating complex molecular interactions that are impossible to handle even with our best supercomputers today. This would slash development timelines and lead to an explosion of innovation in healthcare. In finance, quantum algorithms can improve portfolio optimization and risk assessment in complex markets. Even climate scientists are eyeing quantum-powered models to better understand and predict global weather patterns.

However, quantum computing still faces formidable challenges. The most pressing is quantum decoherence—the tendency for quantum states to decay rapidly due to environmental interference. This limits the time available for computations and introduces errors. Another hurdle is scalability; while current quantum processors boast hundreds or even thousands of qubits (quantum bits), millions may be needed for truly transformative applications. Thus, it’s crucial for potential investors to remember that we’re still very early in this technology’s lifecycle.

Note: We make every effort to keep our information accurate and up-to-date. However, technology markets do move fast and company situations can change rapidly. Please use this guide as an intro to the quantum computing landscape; but ultimately, do your own due diligence before taking action.

Quantum Computer Visual Guide
What a quantum computer looks like. Credit: Aliaksandr Marko/Adobe

Tier 1: Pure-Play Quantum Computing Stocks

These quantum computing stocks represent companies fully dedicated to quantum technologies. While quantum tech is still in its early stages, these pure-plays are racing to achieve practical quantum advantage. Investing here is akin to backing early semiconductor companies. It’s high risk, but potentially the largest returns if quantum computing fulfills its promise.

Rigetti Computing (RGTI)

Rigetti (RGTI) takes a full-stack approach, including in-house chip making and cloud services, to pursue near-term practical uses and steady revenue growth.

Rigetti is a “full-stack” quantum computing company, making everything from the qubits to the user interface. This is like a car company that manufactures its own engines, designs its own software, and sells directly to consumers. The crown jewel of this approach is Rigetti’s in-house Fab-1 chip fabrication facility. Having their own “chip factory” allows Rigetti to rapidly iterate and customize their quantum processors, a big advantage in a fast-moving field.

The company focuses on hybrid quantum-classical computing through their Quantum Cloud Services (QCS) platform. Basically, quantum computers tap in for specialized tasks, while classical computers handle the rest. This strategy doesn’t require waiting for perfect, error-free quantum computers (which are still years away). Instead, it swaps in quantum computers where they’re best suited, and it could unlock practical applications much sooner. Rigetti’s business model emphasizes recurring revenue through this cloud subscription service.

Rigetti recently launched their Ankaa-2 processor, achieving 98% median two-qubit gate fidelity. In plain English, this means their quantum operations are very precise, with only a 2% error rate. The company has a clear scaling strategy based on this Ankaa architecture, with the path to 336+ qubit systems laid out. Rigetti has also introduced the Novera QPU for direct sales to researchers and companies. Think of this like a “quantum computing starter kit” that would speed up R&D in the field.

Rigetti’s near-term goal is achieving “narrow quantum advantage” within 2-3 years. This means a quantum computer that outperforms classical ones on specific, practically relevant tasks. (While Google already claimed quantum advantage in 2019, it was just for a demo task without practical uses.) Their partnerships span government agencies, research institutions, and businesses, providing diverse avenues for growth.

IonQ (IONQ)

IonQ (IONQ) focuses on high-quality “trapped ion” qubits that could enable more complex quantum algorithms and earlier practical uses.

IonQ focuses on trapped-ion quantum computing, which uses suspended ions as qubits. This approach offers advantages in qubit “coherence times” and “connectivity.” Coherence time refers to how long a qubit can maintain its quantum state. Longer times allow for more complex quantum operations (and thus broader use cases). High connectivity means each qubit can easily interact with others (and thus enabling more efficient quantum algorithms).

Jargon aside, in practice, what this means is that IonQ emphasizes quality over quantity of qubits. IonQ’s approach allows them to run longer, more intricate quantum algorithms without losing information to environmental noise. This is crucial for tackling real-world problems that require many computational steps. Think of it like solving a complex puzzle – the longer you can keep all the pieces in play without disturbance, the more likely you are to find the solution.

The company emphasizes achieving high-fidelity operations across a wide range of “circuit depths.” In simpler terms, this means they’re working to perform a long series of precise quantum operations before errors creep in and muddy the results. It’s akin to performing a complex dance routine – the goal is to execute as many precise steps as possible before a misstep occurs. This capability is essential for running quantum algorithms in areas like cryptography and chemical simulations.

IonQ has entered strategic partnerships with major cloud providers including Amazon, Microsoft, and Google. This allows users to access IonQ’s quantum computers through familiar cloud platforms. It’s like being able to rent a supercar through your usual car rental app. This strategy, coupled with IonQ’s emphasis on quality over quantity of qubits, could lead to earlier practical quantum applications.

D-Wave Quantum (QBTS)

D-Wave (QBTS) leads in quantum annealing, showing early commercial success and a unique edge in emerging quantum-AI applications.

D-Wave is the pioneer of quantum annealing, a form of quantum computing specialized for optimization problems. Most other companies in this space are developing “gate-based” quantum computers that use logic gates similar to traditional computers. But quantum annealers work differently. They find “low-energy states” of a system, which you can think of like a ball rolling down a hill. This approach is especially well-suited for tasks such as route optimization, portfolio management, and machine learning.

D-Wave is an early leader in commercializing quantum computing, with over 30 initial business use cases moving into production. Their latest Advantage2 system also has over 5000 qubits, a significant leap in qubit count. To be clear, it’s not an apples-to-apples comparison against competitors, as D-Wave’s quantum annealers are more narrow in use cases. Even so, the company’s steady progress is encouraging at such an early stage.

The company has recently partnered with SavantX to develop quantum generative AI. While it sounds like they just combined two buzzwords, quantum computing and generative AI, it’s actually a natural fit. The idea is to design quantum annealers specifically around boosting generative AI performance. This could bring quantum technology to market faster, especially in drug discovery and logistics. 

D-Wave’s financial performance shows 55% year-over-year growth in quarterly bookings, reaching $4.5 million in Q1 2024. The company has expanded its commercial customer base to 75, including 25 Forbes Global 2000 companies. Their gross profit margin improved from 26.6% to 67.3% year-over-year, indicating smooth monetization of their quantum technology. This financial growth, coupled with their unique focus on quantum annealing, makes D-Wave an intriguing quantum computing stock for investors looking to capitalize on early commercial use cases.

Classical Interface to Quantum Computer
Quantum computers will still use classical user interfaces. Credit: IBM Quantum Computing Lab.

Tier 2: Quantum-Adjacent Tech Companies

This tier features companies developing quantum technologies alongside other tech offerings. These quantum computing stocks reflect the current state of the industry – full of potential, but not quite ready for prime time. By diversifying across quantum and classical technologies, these firms offer a hedge. They can benefit from quantum breakthroughs while pursuing revenue streams from established tech.

Quantum Computing Inc. (QUBT)

Quantum Computing Inc. (QUBT) takes a unique approach with room-temperature quantum systems and accessible enterprise applications.

Quantum Computing Inc. (QUBT), or QCi for short, takes a unique approach by focusing on room-temperature quantum systems. Unlike other quantum companies working on long-term research, QCi aims to integrate with existing IT infrastructure. They focus on Entropy Quantum Computing (EQC), which uses controlled energy loss in a photonic architecture. Think of it as harnessing quantum “noise” that other systems try to eliminate. This allows QCi to deliver quantum capabilities without the extreme cooling typically required, making their systems more accessible and affordable for enterprises.

QCi’s strategy emphasizes a diversified product portfolio spanning quantum computing, AI/ML, remote sensing, imaging, and cybersecurity. For example, their quantum LiDAR could make autonomous vehicles safer and more reliable. Meanwhile, their cybersecurity solutions aim to address growing quantum threats. This breadth gives different revenue streams and reduces reliance on any single one succeeding. QCi also has plans for an Arizona chip foundry, which would give them a vertically integrated edge, similar to Rigetti.

The company has achieved initial product sales and is building a government and commercial pipeline. QCi reported $27,000 in revenue for Q1 2024 with a 42% gross margin, mainly from professional services. While these numbers are tiny, they represent budding traction in a nascent field. With $6.1 million in cash as of March 31, 2024, and $79.3 million in stockholders’ equity, QCi has resources to pursue its ambitious plans. However, with a $6.9 million net loss in Q1 2024, the company will need to scale revenues or secure more funding to reach profitability. QCi’s unique angle could pay off, but at the moment, QCi is a much more speculative play than others on this list.

Arqit Quantum (ARQQ)

Arqit Quantum (ARQQ) focuses on quantum-safe encryption software for cybersecurity, to be implemented before quantum computers become a threat.

Arqit Quantum stands out among quantum computing stocks by addressing a near-term hot button topic in the quantum landscape: cybersecurity. Their focus is on quantum-safe encryption, also known as post-quantum cryptography. Think of it like developing unbreakable locks for a future where quantum computers can pick nearly any current lock. This approach allows Arqit to commercialize quantum-related technology today, before large-scale quantum computers arrive.

The company’s key innovation is its Symmetric Key Agreement platform. Traditional encryption often uses asymmetric methods (different keys for encryption and decryption). But Arqit’s approach uses symmetric encryption (same key for both) with a quantum-safe key distribution method. It’s a secure way to get the same key to both sender and receiver without risk of interception. This software-based solution can work with existing infrastructure, potentially allowing for faster revenue scaling than hardware-focused quantum companies.

Arqit has gained early traction with telecom operators, government agencies, and defense contractors. They reported $119,000 in revenue for the six months ended March 31, 2024, with renewals or extensions from nine existing customers. While these numbers are modest, they represent early adoption in a field where many competitors are still in research phases. With $21.3 million in cash at the end of March 2024, Arqit has resources to continue development, but will need to accelerate revenue growth to reach profitability. Arqit’s focused strategy on quantum cybersecurity gives them a differentiated position with nearer-term revenue potential, but also limits their total addressable market compared to more diversified quantum players.

Google’s large quantum computer. Credit: Google Quantum AI

Tier 3: Tech Giants with Quantum Programs

For a more conservative approach to quantum computing stocks, look to established tech giants with quantum research divisions. These companies recognize quantum’s long-term potential but aren’t betting the farm on it. Their strategy mirrors the overall state of quantum tech: promising, but not yet mature enough to dominate investment. This tier offers exposure to quantum upside while limiting downside risk.

IBM (IBM)

IBM (IBM) leads with an ambitious qubit scaling roadmap, a collaborative quantum ecosystem, and major error reduction progress.

IBM’s quantum strategy hinges on an ambitious scaling roadmap, targeting 4,158 qubits by 2025 with its Kookaburra processor. This aggressive scaling distinguishes IBM in the quantum race. The company employs a full-stack approach: hardware, software, and cloud access. Key elements include the Qiskit open-source development kit and IBM Q System One, the first quantum system for commercial use.

IBM’s quantum network, with over 200 organizations in 19 countries, is a robust ecosystem for collaboration. Key partnerships include simulating lithium-sulfur batteries with Daimler AG and quantum option pricing with JPMorgan Chase.

IBM’s progress in error mitigation and correction is also notable. Using Qiskit Runtime in 2022, they saw a 5x improvement in error rates. This is a crucial step towards the “fault-tolerant” quantum computing needed for practical use cases.

Alphabet (GOOGL)

Alphabet (GOOGL) stands out for its quantum supremacy milestone, strong focus on error correction, and its AI expertise.

Alphabet’s quantum efforts center on developing error-corrected quantum systems. One notable accomplishment is when their 53-qubit Sycamore processor claimed quantum supremacy in 2019. That year, it completed a specific calculation in 200 seconds versus an estimated 10,000 years for classical supercomputers. Although it was just for a demo task (and not a practical one), it was an extremely encouraging milestone.

Alphabet’s quantum strategy also leverages its AI and machine learning expertise. They’ve released TensorFlow Quantum, which merges quantum algorithms with classical machine learning. They’ve also developed the “surface code” approach for more stable logical qubits. (It’s considered one of the more promising approaches for large-scale quantum error correction.)

Like IBM, Alphabet is pursuing real-world applications, such as optimizing traffic flow with Volkswagen. Their Cirq framework has surpassed 500,000 downloads since it was released in 2018.

Microsoft (MSFT)

Microsoft (MSFT) has a unique long-term bet on topological qubits, as well as a strong cloud-based quantum ecosystem.

Microsoft’s quantum strategy is defined by its long-term focus on topological qubits. This is a potentially revolutionary approach promising enhanced stability against environmental noise. Recent progress in topological superconductivity suggests potential for error rates 10,000 times lower than conventional superconducting qubits.

However, topological qubits are still extremely early in development, more so than other qubit approaches. That means Microsoft’s hardware angle is still mostly speculative.

In the interim, Microsoft leverages its cloud expertise through the Azure Quantum platform. The platform provides access to diverse quantum hardware and software options, and its user base spiked by 300% in one year in 2021. Over 100,000 developers now use Microsoft’s Q# programming language.

Honeywell (HON) via Quantinuum

Honeywell’s (HON) majority stake in Quantinuum combines trapped-ion expertise with software capabilities, achieving industry-leading quantum volume.

Honeywell’s quantum strategy revolves around its 54% stake in Quantinuum. The spin-off combines Honeywell’s trapped-ion hardware expertise with Cambridge Quantum’s software. This vertically integrated approach allows Honeywell to benefit from a specialized entity. Honeywell’s ongoing contributions in ultra-high vacuum chambers and precision controls also remain crucial for Quantinuum’s hardware advancements.

Quantinuum’s H-series quantum computers have achieved industry-leading quantum volume measurements. This is a comprehensive metric tyat takes into account both the number of qubits and their quality.

Quantinuum’s practical focus is in products like Quantum Origin, the first commercial quantum cryptographic key generation platform. The company also has extensive work in quantum natural language processing and quantum chemistry simulations.