IaaS (infrastructure as a service)
Also called infrastructure as a service.
Renting raw computing, storage and networking from a cloud provider, while you manage everything that runs on it.
Last updated
What it is.
With IaaS the provider runs the data centres, physical servers and network. You get virtual machines, disks and networks on demand and pay for what you use. You install and patch the operating system, the database and your app yourself.
NIST's cloud definition names three service models. IaaS gives you the most control and the most work. The other two hand more of the stack to the provider: a platform where you only deploy code, and finished software you just log in to.
Why it matters
IaaS decides how much of the running cost is your team's time. It is flexible and often cheaper per unit of compute, but someone has to own patching, backups, scaling and security for every machine. That ongoing work belongs in the total cost of ownership.
In a product build
We usually start on managed services and drop to IaaS only where a workload needs it, such as custom runtimes, special hardware or steady high load. When we do, the machines are defined with infrastructure as code so they can be rebuilt.
Common mistakes.
- 01
Picking IaaS for control and then not staffing the patching and on-call work it brings.
- 02
Building servers by hand, so nobody can recreate them after a failure.
- 03
Leaving machines running at full size around the clock when load is low most of the day.
Read the official text.
Primary sources this definition is based on.
- NIST SP 800-145, The NIST Definition of Cloud Computingchecked 2026-10-25
Related terms.
- ServerlessA cloud model where the provider runs your code on demand and manages the servers, and you pay for what you use rather than for idle machines.
- Container (software)A package that holds an application and everything it needs to run, isolated from other software on the same machine.
- AutoscalingAutomatically adding or removing computing capacity, such as servers or containers, as the load on a system goes up or down.
- Infrastructure as code (IaC)Defining servers, networks, databases and other cloud resources in code files that are versioned and applied automatically, instead of setting them up by hand.
- Total cost of ownership (TCO)Everything a piece of software costs over its life, not just the price to build or buy it.
Guides and pages
Browse the full glossary or read answers to common questions.
