Quantum computing
How quantum computers work and what it takes to make them useful.
Quantum computing uses the behaviour of quantum states to tackle particular calculation problems. Its basic unit, the qubit, can hold a combination of states, and a calculation controls how those states interact before the result is measured. Because noise and imperfect controls introduce errors during this process, adding qubits helps only if the machine can use them reliably.
The challenge of building a reliable machine creates work for control-electronics, laser, cooling, software and integration suppliers, alongside companies selling complete computers or cloud access. Quantum physics also supports communication and sensing, but for different tasks: transferring quantum information or measuring quantities such as time and magnetic fields. Their customers and routes to revenue differ from computing, so they need to be treated as separate markets.
Market size & opportunity
For computing specifically, McKinsey’s April 2026 Quantum Technology Monitor estimates worldwide supplier revenue above US$1 billion in 2025 and projects US$43–71 billion in 2035. The range covers hardware, software and services. It excludes the economic benefits customers might gain, because potential savings, research funding and suppliers’ sales are different measures rather than amounts to add together.
Some of this activity already happens while quantum computers are being developed. Researchers need control electronics, lasers and other equipment to build and test their machines. Companies supplying those tools are therefore part of the field even if they do not make a complete quantum computer.
Market outlook
Quantum computing revenue
Worldwide · US$ billion per year
- 2025Study baseline> 1
- 2035Forecast43–71
Hatched area shows the forecast range
The study estimates 2025 computing revenue above US$1 billion and gives a future range rather than a single target. Both cover hardware, software and services, excluding the economic benefits customers might gain.
McKinseyForecast published
Recent progress
Reducing errors is one of the steps needed to make those computers more useful. A Nature Physics paper published on 13 July 2026 demonstrated error correction within a single atomic ion by using additional internal states. It extended the encoded qubit’s lifetime by up to 1.5 times compared with an unencoded qubit. That is progress in a laboratory, but the benefit still needs to carry through to a complete machine performing a useful calculation.
Sources
- IBM · Quantum computing fundamentals
- McKinsey · Quantum Technology Monitor, April 2026
- Nature Physics · Error correction in a single atomic ion, July 2026
Updated
Research & reports
IQM, Quantinuum and Creotech: getting to know Europe’s quantum computing industry
A quantum computer uses the behaviour of matter at very small scales to process information in a different way. Researchers are developing these machines to tackle certain problems that today’s computers struggle to solve.
From CERN roots to quantum control: Creotech Quantum S.A.
The Warsaw company sells the electronics that tell scientific equipment what to do and precisely when to do it. Its next challenge is helping quantum computers grow beyond the laboratory.