From Errors to Expectations
Enter the error rate and qubit count of the quantum computing hardware to see an estimate of how large a computation can be before errors dominate and the computational results become too unreliable.
Today's Quantum Hardware
These are the main hardware approaches currently competing, though others are also being explored.
Current Quantum Computers1
| # Physical Qubits | Error Rate 2 | Hardware Type |
|---|---|---|
| 98 | 3×10⁻⁴ | Trapped-Ion |
| 156 | 5.19×10⁻⁴ | Superconducting |
| 260 | 1.36×10⁻³ | Neutral Atom |
1 Examples of the largest universal, gate-based quantum computers on the three currently most advanced hardware architectures. 2 The two-qubit gate error rate of the hardware.
Historic error rate progress
Two-qubit gate error rates have dropped roughly 10× per decade across all three platforms.
Historic physical qubit count
The number of physical qubits per processor has grown steadily across all three platforms.
Switch to Expert Mode above for full historic charts and projections.
The Gap: What We Need vs. What We Have
Here are some examples of quantum algorithms that promise real advantages, this is a curated and incomplete list. Use your own AI agent to explore how far away specific claims really are.
Example Problems
| # Qubits | # Computational Depth | Problem |
|---|---|---|
| 1399 | 6.5×10⁹ Toffoli Gates | Factoring RSA-2048 |
| 1200 | 9.0×10⁷ Toffoli Gates | Breaking ECC-256 (secp256k1)† |
† Attested estimate. The source withholds the circuit, so this figure cannot be independently reproduced. Hover the marker for what is and is not attested.
Explore with your own AI
Let your AI assistant investigate quantum-computing questions using this site's data and tools.
How this works & MCP
The /api/expectation endpoint is open, has no authentication, and is allowed by robots.txt. CORS is wide open. Any agent that can fetch a URL can use it.
The /agent.txt page tells the agent how to call it. The agent gets back the same math, the same assumptions, and the same source URLs you see on this page, meaning you can verify every answer yourself.
Examples
Can today's hardware crack RSA-2048?
Test the most-hyped quantum use case against real hardware numbers.
When might fault-tolerant quantum computing arrive?
Project hardware trends to estimate when error correction becomes practical.
Analyze a quantum computing claim
Paste a paper or article URL and let your agent fact-check it.
Which hardware approach is winning?
Compare trapped-ion, superconducting, and neutral atom progress.
The full machine-readable list (with math constants and historic series) is available at /api/expectation.