How do I open an .mpp file without Microsoft Project?

ProjectLibre is free, open source, and imports most .mpp files including the Gantt chart. For simply reading a schedule, asking for a PDF or Excel export from Project is easier still.

Is Microsoft Project included in Microsoft 365?

No. Project is licensed separately from the normal Office applications, which is why so few people can open an .mpp they have been sent.

File extensions

How to open a .mpp file

Microsoft Project plan · Project management

An .mpp file is a Microsoft Project plan. Project is a separate paid product, not part of Office. ProjectLibre opens most .mpp files for free and is the practical answer.

What a .mpp file actually is

MPP stores a project schedule: tasks, durations, dependencies, resources and costs. It is the file behind every Gantt chart produced in Microsoft Project.

The format is proprietary and undocumented, so third-party support is reverse-engineered and fidelity varies with how complex the plan is.

Why it will not open

Microsoft Project is not included in any normal Office or Microsoft 365 subscription. It is licensed separately, which is why a plan mailed around an organisation opens for two people and nobody else.

Renaming it to an extension you can open will not help: changing the extension does not convert the file, it only changes what Windows tries to open it with.

Step by step

Windows

01Install ProjectLibre, which is free and open source, and open the .mpp directly. Tasks, dependencies and the Gantt chart come through.
02GanttProject is another free option, though its MPP import is weaker.
03If you only need to read the schedule, ask the sender to export to PDF or Excel from Project. That is often all anyone actually needs.
04Very complex plans with custom fields and levelling may not import cleanly anywhere but Project itself.

macOS

01Microsoft Project has never had a macOS version.
02ProjectLibre runs on macOS via Java and is the main free route.

Programs that open .mpp

Taken straight from publisher manifests. Some of these handle the format for a narrow purpose rather than as their main job.

foobar2000v2.25.10 · 3 hashed installers100

Common questions

How do I open an .mpp file without Microsoft Project?: ProjectLibre is free, open source, and imports most .mpp files including the Gantt chart. For simply reading a schedule, asking for a PDF or Excel export from Project is easier still.
Is Microsoft Project included in Microsoft 365?: No. Project is licensed separately from the normal Office applications, which is why so few people can open an .mpp they have been sent.