Now Available: Central download statistics for OSS projects

December 15, 2010 By Brian Fox

Maven Central contains over 260,000 artifacts and serves over 70 million downloads every week. It has become the principal resource for exchanging Java artifacts with demand doubling year over year. Getting artifacts into Central is the most effective way to get your software to developers since every build tool that can download Java libraries knows where to look for a world of libraries and dependencies, and that single, authoritative place is Maven Central.

Earlier this year, we announced the availability of official repositories in the UK to improve performance for the users in Europe. Today we are making the artifact download statistics available to the projects whose artifacts are served by Central. This has been one of the most frequently requested features by project teams. Since the raw Central logs are larger than seven gigabytes every day, processing this data is no small undertaking.

The statistics are available to all projects hosted using Nexus at, and These three avenues represent the majority of projects actively contributing artifacts. Nexus’ security mechanism already in place on these instances provides a mapping of repository path to project which allowed us to easily roll up the counts for each team. Read more to find out how to access your project’s statistics.

Accessing Your Project’s Statistics

Current OSSRH, Apache and Codehaus users don’t need to do anything to gain access to these statistics. If you have deployer permissions for your project, you should already be able to see the Central Statistics link in the Views/Repositories section in the left-hand menu area. NOTE: In some cases, users with early access to the plugin have reported needing to click the web browser’s Refresh button before seeing the link.

Clicking on the Central Statistics link will open a tab showing you:

  • a line chart depicting the volume of raw downloads of your artifacts from Central over the past 12 months
  • a pie chart breaking down the last month’s worth of downloads of your project by artifactId
  • a sortable grid containing the counts that generated the pie chart

If you only have access to a single project with a single groupId, the page will be fully populated upon opening the tab. If you have access to multiple projects or a project encompassing multiple groupIds, you will need to select a project and groupId on which to report. You can also use artifactId and version combo boxes to further narrow down the reporting scope for the timeline, the pie chart, and the grid.

The pie chart and grid can be further constrained by a date range combo box that defaults to the last month, but can be used to report on the last 3, 6, 9, or even 12 months or to select a single month for reporting.

Finally, the plugin offers two types of reports. Downloads is the default and simply reports on the number of successful downloads of your artifacts. Unique Ips is the second report type and gives an idea of how many unique users are downloading your artifacts. It is also possible to export the raw data to CSV so that you can analyze it using your own favorite tool.

Frequency of Update

Currently we generate the statistics to a granularity of a single month, so you can expect to see the new results appear within a few days of each new month.

Send us Suggestions and Feedback

This is just the first release of this plugin, and we invite your feedback and recommendations, not just on how to improve the look and feel of the plugin but also for new reports you’d like to see in the future. You are welcome to create issues in the following JIRA project:

When creating issues, please assign them to the “Central Statistics Plugin” component.

  • Vincent Massol

    Great! Is this available in Nexus by default (i.e. to be used for your own repository) and if so, in which version of it? Thanks for a cool feature.

    • Brian Fox

      Currently no since the stats logic is built independent of Nexus because these logs are independent.

      • Vladimir Velinov

        apart from this stats plugin is there another way to check the unique IPs on my own repository?

  • Guillaume Laforge

    I’d be curious to know a little more about how the statistics are computed.
    When I look at the Groovy project, I’m not sure I really understand the numbers I see.
    Groovy being downloaded 10M in a month sounds a bit bizarre, despite Groovy’s success.
    From “just” the raw logs from Codehaus, I know Groovy can be downloaded up to 185K in a month (current record), with an average >100K… but 10M in month?
    I’m sure Groovy’s downloaded way more from Maven Central than from the binary distribution offered by Codehaus, but still, I think there’s something odd with the numbers.
    I’d be happy to know if I can be of any help to make sure the numbers are a bit more realistic.

    • Brian Fox

      We’re investigating, but my initial analysis shows a staggering number of repeated pom downloads coming from Ivy users. I imagine there’s something going on in Ivy that is preventing it from caching the pom and querying it on each lookup.

    • Brian Fox

      I filed a bug for the Ivy stuff I saw, and we’ll adjust our stats counting to correct for this.

  • Geoffrey De Smet

    Very nice improvement :)

    “If you have deployer permissions for your project, …”

    Why can’t just anyone see them? Why not make them open (as in open source) to normal users?

    Why bother us, the open source developers, with authorization requirements if we just want to see our download statistics?