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Compute4 min readUpdated August 18, 2026

Cloud Run

In one sentence

Cloud Run takes a container, runs it when requests arrive, scales it automatically, and charges you nothing while it sits idle.

What it is

Cloud Run runs containers as a managed service. You provide a container image that listens for HTTP requests on a port; the platform handles provisioning, scaling, load balancing, TLS certificates and availability. There are no servers, clusters or node pools to configure.

Because the unit of deployment is a standard container, you are not restricted in language or framework. If it runs in a container and serves HTTP, it runs here — which makes it far less constraining than earlier generations of serverless platforms.

Why it matters

For a large share of web services and APIs, Cloud Run is the shortest distance between working code and a production deployment. It removes a category of operational work — patching, capacity planning, cluster upgrades — that produces no value for most teams.

The economics matter as much as the convenience. Scaling to zero means a service with no traffic costs nothing. For internal tools, low-traffic APIs and development environments, this frequently changes the total cost by an order of magnitude compared with an always-on virtual machine.

Key concepts

  • Service — a deployed container with a stable HTTPS URL. Each deployment creates a new immutable revision.
  • Revision — a specific version of the service, including its image and configuration. Revisions are immutable, which makes rollback instant.
  • Traffic splitting — sending a percentage of requests to a specific revision. This is what makes canary releases straightforward.
  • Concurrency — how many simultaneous requests one container instance handles. Unlike most function platforms, this defaults well above one, which changes the cost model significantly.
  • Cold start — the delay when a request arrives and no instance is running. Minimum instances keep containers warm at the cost of paying for idle capacity.
  • Minimum and maximum instances — the floor that controls cold starts and the ceiling that protects downstream systems and your budget.
  • Jobs — for work that runs to completion rather than serving requests, such as scheduled batch processing.
  • Service identity — each service runs as a service account; give it only the permissions the code actually needs.

Choosing between compute options

ChooseWhenTrade-off
Cloud RunStateless HTTP services, APIs, event handlers, spiky or low traffic.Request-driven model; long-running background work needs a different shape.
GKEComplex multi-service systems, specific networking or scheduling needs, existing Kubernetes investment.Substantially more operational surface to understand and maintain.
Compute EngineFull operating system control, licensed software, stateful long-running processes.You own patching, scaling configuration and availability design.

The exam framing is usually about operational burden rather than capability. When a scenario mentions a small team, a desire to minimise operations, or unpredictable traffic, the fully managed option is generally the intended answer.

Common use cases

  • Public REST and GraphQL APIs that scale with demand and cost nothing overnight.
  • Server-rendered web applications behind a global load balancer.
  • Event handlers triggered by messages, storage changes or scheduled jobs.
  • Internal tools that are used a few times a day and should not run a server continuously.
  • Batch processing as a job — data transformation, report generation, scheduled maintenance.

Certification relevance

Where this topic appears, and how deeply each exam goes into it. These are our own assessments based on published exam guides.

Practice questions

Compute practice questions

9 original questions with full explanations.