Welcome to CloudKitty’s documentation!

What is CloudKitty ?

CloudKitty is a Rating-as-a-Service project for OpenStack and more. The project aims at being a generic solution for the chargeback and rating of a cloud. Historically, it was only possible to operate it inside of an OpenStack context, but it is now possible to run CloudKitty in standalone mode.

CloudKitty allows to do metric-based rating: it polls endpoints in order to retrieve measures and metadata about specific metrics, applies rating rules to the collected data and pushes the rated data to its storage backend.

More details about concepts, expressions, and jargons can be found in the documentation of CloudKitty concepts.

CloudKitty is highly modular, which makes it easy to add new features.


We’re looking for contributors! If you want to contribute, please have a look at the developer documentation .

What can be done with CloudKitty ? What can’t ?

With Cloudkitty, it is possible to:

  • Collect metrics from OpenStack (through Gnocchi) or from somewhere else (through Gnocchi in standalone mode and Prometheus). Metric collection is highly customizable.

  • Apply rating rules to the previous metrics through the hashmap module or custom scripts. This is all done via CloudKitty’s API.

  • Retrieve the rated information through the API, grouped by scope and/or by metric type.

However, it is not possible to:

  • Limit resources in other OpenStack services once a certain limit has been reached. Ex: block instance creation in Nova above a certain price. Cloudkitty does rating and only rating.

  • Add taxes, convert between currencies, etc… This needs to be done by a billing software. CloudKitty associates a price to a metric for a given period, but the price’s unit is what you decide it to be: euros, dollars, cents, squirrels…

What changes/features are to expect ?

If you’re interested in CloudKitty’s evolution, see the project’s roadmap .

Documentation contents

Documentation type

Table of contents


End User

Admin / Operator



API Reference