Public Quantum Computers Ranked by Available Qubits
This is a spec ranking, not a financial one, and it comes with the most important caveat in quantum computing: raw qubit counts are not comparable across technologies. D-Wave's thousands of annealing qubits solve a different (narrower) class of problems than a gate-based machine, and 100 high-fidelity trapped ions can outperform many more noisy superconducting qubits. That said, "who has the most qubits" is the question everyone asks, so here is each public company's flagship system ranked by physical qubit count, with modality and two-qubit gate fidelity shown so the numbers can be read in context. Under the current rule, “flagship system” means the best currently available system from each company, not a roadmap target.
Hardware verified · market data updates live
Not ranked under the current-available physical-system rule: QUBT, ARQQ, QSI, XNDU, HQ, BTQ.
The companies, in order
1. D-Wave Quantum (QBTS) — 5,627
Advantage_system4 · Available in Leap · Annealing qubits · D-Wave Advantage_system4 specifications ↗
D-Wave is the world's first commercial quantum computing company, specializing in quantum annealing technology for optimization problems. Its systems are used in logistics, finance, and drug discovery.
Fidelity context: Gate fidelity does not apply to quantum annealing.
QBTS live data, financials & filings →2. IQM Quantum Computers (IQMX) — 150
Radiance 150 · Available to order · Physical qubits · IQM Radiance specifications ↗
IQM Quantum Computers is Europe's largest quantum computing hardware company, building on-premises superconducting quantum computers for national labs, HPC centers and universities — with systems delivered across Finland, Germany, Spain, Poland, South Korea, Taiwan and beyond. It operates its own chip fabrication facility in Espoo, Finland.
Fidelity context: Typical median CZ specification for the 150-qubit configuration.
IQMX live data, financials & filings →3. Rigetti Computing (RGTI) — 107 active
Cepheus-1-108Q · Generally available · Physical qubits · Rigetti Q2 2026 results ↗
Rigetti Computing is a full-stack quantum-classical computing company using superconducting qubits. It fabricates its own chips at Fab-1 and provides cloud access through Quantum Cloud Services (QCS).
Fidelity context: Q2 2026 company-reported approximate medians for Cepheus-1-108Q; approximately 60 ns gate speed.
RGTI live data, financials & filings →4. Infleqtion (INFQ) — 100+
Sqale (2025) · Operational · Physical qubits · Infleqtion Sqale specifications ↗
Infleqtion (formerly ColdQuanta) designs and builds quantum computers, precision sensors, and quantum software using cold atom and neutral atom technology. Its Sqale quantum computer has been commercially deployed at the UK National Quantum Computing Centre.
Fidelity context: Representative CZ fidelity with post-selection; 98.8% raw. Best published result: 99.73%.
INFQ live data, financials & filings →5. Quantinuum (QNT) — 98
Helios · Available now · Physical qubits · Quantinuum Helios specifications ↗
Quantinuum develops trapped-ion quantum computers and quantum software, spun out of Honeywell in 2021. Its H-Series and Helios systems hold world records in gate fidelity and quantum volume. Software platforms include InQuanto (quantum chemistry), Quantum Origin (cybersecurity entropy), and lambeq (quantum NLP/AI). IPO: Nasdaq June 2026.
Fidelity context: Average two-qubit gate fidelity across all qubit pairs.
QNT live data, financials & filings →6. IonQ (IONQ) — 36
Forte Enterprise · Commercially available · Physical qubits · IonQ Forte Enterprise specifications ↗
IonQ develops trapped-ion quantum computers accessible via cloud through AWS Braket, Azure Quantum, and Google Cloud. The company builds full-stack quantum hardware and software targeting fault-tolerant quantum computing.
Fidelity context: Commercial Forte Enterprise specification.
IONQ live data, financials & filings →Methodology: Ranks each company's largest currently available physical-qubit system. “Available” means operational, generally available, commercially available, or offered as a current orderable product with published specifications. Roadmap targets, pre-sale target specifications, third-party hardware, analog variables, and logical-only demonstrations are excluded. Annealing and gate-model qubit counts are labeled because they are not directly comparable. Covers the US-listed pure-play quantum universe tracked by this site. Full metric definitions on the methodology page. Not investment advice.
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