Computing · Projected milestone
Thousands of logical qubits
60% by 2040 · including earlier years
The year is an editorial timing estimate. The percentage applies to occurrence by the stated deadline. These estimates are not calibrated odds.
Large fault-tolerant quantum computers run useful algorithms.
Explore this milestone on the interactive mapWhat the forecast means
Milestone stage: demonstration
unknown
Thousand-scale fault-tolerant logical computation.
Completion criteria: Audited execution establishes logical rather than physical qubit count, sustained operation depth, logical error rates and reproducible algorithmic results. A roadmap or simulator does not count.
This page describes a forecast, rather than an achieved result. Read the methodology and assumptions.
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Sources & evidence
- IBM goes big to keep quantum computers cold 2026-08-20
IBM reports connected cryogenic modules and retains a 2029 Starling target. Processor integration was still a next step; cooling infrastructure does not establish hundreds of fault-tolerant logical qubits.
- IBM Quantum 2030 technology roadmap 2026-03
IBM describes targets including Starling in 2029 and larger logical-qubit systems thereafter. They are engineering plans subject to change, not achieved results.
Record reviewed 2026-10-18