OpenCost

OpenCost is a free, vendor-neutral cost allocation system for Kubernetes and connected cloud infrastructure. It suits platform, finance, and engineering teams that already operate Kubernetes with Prometheus and need container-level showback or chargeback. Its broad coverage and open-source licensing are compelling, but delayed provider billing data makes it a poor substitute for final cloud-account reconciliation.

Overview

OpenCost attributes infrastructure spending to Kubernetes concepts and individual containers, giving teams a practical basis for internal reporting, showback, and chargeback. It covers CPU, GPU, memory, load balancers, and persistent volumes, while also monitoring cloud resources outside Kubernetes. That combination is useful when shared cluster spending must be assigned to applications or teams rather than viewed only as one provider bill.

The project is vendor-neutral and a Cloud Native Computing Foundation incubating project. Kubernetes cost reporting is real time, but cloud costs depend on provider billing data arriving, usually several hours to 24 hours later. OpenCost also uses on-demand list prices without reconciling them to billed actual costs, so it is strongest for operational visibility and allocation, not closing the books.

Key features

• Granular allocation: CPU, GPU, memory, load balancer, and persistent-volume costs can be assigned at Kubernetes and container level. This supports detailed ownership reporting, although billing-data delays still affect cloud-backed figures.
• API and web interface: The API supplies real-time and historical Kubernetes cost reports using on-demand prices and cloud provider cost and usage reports. The UI arrives with the default installation and visualizes Kubernetes allocations alongside related cloud costs, giving teams both automation and an immediately usable view.
• Broad provider coverage: Integrations cover Alibaba, Amazon Web Services, Google Cloud Platform, Microsoft Azure, Open Telekom Cloud, Oracle Cloud Infrastructure, OVHcloud, Scaleway, and STACKIT. The integrations page also lists Prometheus, Cortex, Thanos, Victoria Metrics, Grafana, and Grafana Cloud for metrics and visualization workflows.
• Operational integrations: The MCP server gives AI agents access to allocation, asset, and cloud-cost data and is enabled by default in deployments. For AWS, IAM roles for service accounts use ambient credentials, avoiding secrets in the configuration file.
• Deployment requirements: OpenCost requires a Kubernetes cluster and Prometheus; the project recommends Helm for full functionality. That is a sensible fit for established platform teams, but a substantial prerequisite for organizations without that stack.

Pricing

OpenCost — free. The plan is open source under the Apache 2.0 license and has no software charge. There is no free trial because the product itself is free. The trade-off is infrastructure and operational responsibility: you provide the Kubernetes and Prometheus environment and manage the deployment.

This pricing fits teams that can self-host and want unrestricted use of an open project rather than a metered SaaS service. It is less suitable for buyers seeking a turnkey, vendor-managed cost platform. Cloud costs are also unavailable for on-premises clusters, although costs from other cloud providers may be configured.

Platforms

OpenCost supports API, Linux, self-hosted, and web deployments. The included web UI and API make it workable for browser-based analysis and automation, while the self-hosted model keeps deployment in your Kubernetes environment. Prometheus remains a required part of that environment.

Who it's for

Choose OpenCost if your organization already runs Kubernetes and Prometheus and needs transparent allocation down to workloads or containers. It is particularly well suited to platform teams implementing showback or chargeback across multiple supported clouds, and to engineering groups that need API access for historical and real-time reporting.

Look elsewhere if you need cloud billing figures to arrive immediately, must reconcile estimates with provider invoices, or run only on-premises clusters. OpenCost's deployment requirements also make it a poor starting point for teams without Kubernetes operations experience.

Pros and cons

Pros

• Free Apache 2.0 software: There is no license bill or seat charge, making broad internal adoption practical.
• Container-level visibility: Detailed allocation across compute, memory, storage, GPUs, and load balancers supports meaningful ownership reports.
• Wide ecosystem: Multiple cloud providers, Prometheus-compatible systems, Grafana options, an API, and an included UI accommodate existing tooling.
• Credential-conscious AWS integration: IAM roles for service accounts avoid storing AWS secrets in configuration.

Cons

• Requires Kubernetes and Prometheus: Teams without that foundation face deployment work before seeing value.
• Cloud data is delayed: Provider billing information generally takes several hours to 24 hours to appear.
• Estimates are not invoice-reconciled: On-demand pricing is not currently matched to billed actual costs.
• No on-premises cloud-cost support: Cloud costs for on-premises clusters are not supported.

Alternatives

Kubernetes Cost Management Software and Cloud Cost Management Software provide broader category shortlists when OpenCost's self-hosted model is not the right fit.

• KubeAdapt is a freemium option with a free allowance covering the first 100 vCPU across an account, all features, and email support, plus a free trial.
• Atmosly Kubernetes Cost Optimization suits a small personal deployment: its free plan covers one cluster, one cloud account, one seat, one project, two environments, and ten applications, with cost recommendations view.
• PerfectScale offers a free tier up to 200 vCPU per month with unlimited clusters, nodes, and pods; its Expert tier is quote-based.
• Krossboard is another freemium self-hosted/API/web alternative.
• KubeLedger provides free self-hosting for internal use under its stated terms.
• Podledger offers a forever-free community plan for self-hosting, a single cloud, basic dashboards, and pod-level visibility.
• CloudBolt has a free CloudBolt CMP tier with core capabilities for up to 100 resources.
• Klustercost is a free, GPL-3.0 open-source alternative.

Verdict

OpenCost is the right choice for Kubernetes teams that want no-license-cost, container-level allocation across a broad cloud ecosystem and can operate the required stack themselves. Choose it for showback, chargeback, and ongoing visibility; look elsewhere when invoice-accurate, immediate cloud billing or on-premises cost coverage is central to your reporting.