ARQQ vs QSI: Which Quantum Stock Is Better?
Arqit Quantum (Quantum Security) vs Quantum-Si (Quantum Biology) — live market, SEC financial and quantum-hardware data side by side.
ARQQ is the larger company at $505.24M market cap, about 2.5× the size of QSI ($201.23M).
QSI reports more revenue ($2.44M vs $530.0K for ARQQ, latest fiscal year).
On cash runway — the metric that decides who needs to raise money first — QSI is stronger (24mo vs 15mo).
| Metric | ARQQArqit Quantum | QSIQuantum-Si |
|---|
| Market |
| Price | $29.72 | $0.9241 |
| Market Cap | $505.24M | $201.23M |
| 1Y Return | -14.3% | -51.4% |
| 52W High | $62.00 | $3.10 |
| 52W Low | $11.52 | $0.69 |
| Financials |
| Revenue (latest FY) | $530.0K | $2.44M |
| Revenue YoY | +80.9% | -20.3% |
| Net Income | $-35,343,000 | $-101,339,000 |
| Cash & Equivalents | $36.98M | $190.40M |
| Cash Runway | 15mo | 24mo |
| Risk |
| Going Concern Flag | No | No |
| ATM Offerings (dilution) | 26 | 29 |
| Daily Short Vol % | 65.3% | 38.8% |
| Beta (1Y vs SPY) | 1.34 | 1.35 |
| Government & Research |
| Federal Awards Total | $0 | $30.30M |
| Academic Citations | — | — |
| Patents | — | — |
| Quantum Technology |
| Physical Qubits | — | — |
| Qubit Modality | — | — |
| 2Q Gate Fidelity | — | — |
| Cloud Platforms | SKA-Platform (SaaS), SKA-PI (Private Instance) | — |
| Roadmap Target | Global enterprise and telco rollout via SKA-CC for MSPs and sovereign private deployments | Proteus commercial launch late 2026 (18+ amino acids, ~1,000× throughput); 20 of 20 amino acids by 2027 |
| Company |
| Founded | 2017 | 2017 |
| Headquarters | London, UK | Guilford, CT |
| Employees | — | — |
ARQQ vs QSI FAQ
Is ARQQ or QSI the bigger company?
ARQQ is larger, with a market cap of $505.24M versus $201.23M for QSI.
Which has the longer cash runway, ARQQ or QSI?
ARQQ's cash runway is 15mo and QSI's is 24mo (current cash ÷ trailing-twelve-month operating burn; "CF+" means cash-flow positive).
What technology do ARQQ and QSI use?
Arqit Quantum (ARQQ): Quantum Security. Quantum-Si (QSI): Quantum Biology. Qubit counts are not directly comparable across different modalities.
Go deeper
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