How to edit an .mpp file without Microsoft Project
You were sent a Microsoft Project schedule and need to change it, but you don’t have Project or a Windows PC. Here is how to edit the file and send it back.
Updated 17 October 2026
Quick answer
Open the .mpp in an app that can write the format, such as MPP Studio on Mac or iPad. Edit durations, dates, links and progress in a Project-style grid, then save with ⌘S. The file stays an .mpp and opens in Microsoft Project on Windows.
Viewing is easy. Saving is the hard part.
Plenty of tools can read an .mpp file. Far fewer can write one. Most project apps import the file into their own format and, at best, export Microsoft Project XML. That works, but whoever sent you the .mpp gets a different file back and has to import it again.
If the schedule belongs to a client or the main contractor, you usually want to return the same kind of file you received: an .mpp.
Edit it on a Mac or iPad
- Open the .mpp in MPP Studio (double-click it in Finder, or tap it in the Files app on iPad).
- Edit in the grid like you would in Project: type a duration such as 5d, change a start date, link tasks with a predecessor such as 4FS+2d, indent and outdent, add milestones. Dependent tasks move with the change.
- Record progress: actual start, actual finish and % complete. If the plan has a baseline, the forecast finish is compared with it.
- Save with ⌘S. The file stays an .mpp, saved where it came from.
The edits people make most
| TO … | DO THIS |
|---|---|
| Move a task later | Change its start date, or add lag to its link: 4FS+3d. Linked tasks follow. |
| Make a task longer | Type the new duration (8d, 2w). Successors reschedule. |
| Add a task | Insert a row, name it, give it a duration and a predecessor. |
| Add a milestone | Insert a milestone; it has zero duration and shows as a diamond. |
| Link two tasks | Type the predecessor’s ID in the Predecessors column, or drag from one bar to the other. |
| Assign a resource | Pick resources in the inspector; their load shows on the Resources screen. |
| Record progress | Set % complete or actual dates in the grid or the inspector. |
What survives the round trip
Files from Project 2010 through Microsoft 365 open, and saved files open in Microsoft Project on Windows as the sender expects.
| IN THE FILE | KEPT ON SAVE |
|---|---|
| Tasks, outline (WBS), summaries and milestones | Yes |
| Links: finish-to-start, start-to-start, finish-to-finish, start-to-finish, with lags | Yes |
| Durations, constraints and task calendars | Yes |
| Project and resource calendars, holidays | Yes |
| Resources and assignments | Yes |
| Baselines, actual start and finish, % complete | Yes |
| Notes, custom fields and their names | Yes |
| Gantt view columns | Yes |
Other ways, and their catch
| WAY | CATCH |
|---|---|
| Online .mpp editors | The file is uploaded to a third-party server, and many only export XML. |
| ProjectLibre (free, desktop) | Opens .mpp but saves its own format or Project XML, not .mpp. No iPad. |
| OmniPlan Pro, Merlin Project | Good apps that convert the plan into their own document; .mpp is an import and export format. |
| Windows in Parallels + Project | The real thing, but you pay for Parallels, Windows and Project, and it only runs on a Mac. |
Questions people ask
Can I edit an .mpp file online for free?
Some websites can, but your schedule is uploaded to their servers and many save only XML. MPP Studio edits the file on your Mac or iPad.
Will the file still open in Microsoft Project?
Yes. MPP Studio saves the .mpp format, and the file opens in Microsoft Project 2010 through Microsoft 365.
Can I create a new .mpp from scratch?
Yes. Choose File › New (⌘N); new schedules are saved as .mpp files.
Edit your .mpp now
Open, change and save Microsoft Project files natively on Mac and iPad.
Related
Microsoft and Microsoft Project are trademarks of Microsoft Corporation. MPP Studio is not affiliated with Microsoft. Other product names are trademarks of their owners. Competitor details are taken from their own websites and App Store listings in October 2026; check with the vendor for current prices.