PBIR vs PBIR-Legacy
Power BIPBIR saves a report as a folder with a file for each page, visual and bookmark. PBIR-Legacy is the older single report.json. PBIR is now the default.
The two formats
PBIR-Legacy keeps the whole report definition in one file, report.json, at the root of the report folder. It does not support editing outside Power BI Desktop.
PBIR replaces it with a definition folder, where each page, visual and bookmark is its own file. Microsoft documents the format, and other tools may change it.
The version in definition.pbir decides what is allowed. Version 1.0 means PBIR-Legacy only. Version 4.0 or above allows either format.
What a PBIR report folder holds
definition/pages/pages.json, then a folder per page with itspage.json.definition/pages/[page]/visuals/[visual]/visual.json, andmobile.jsonwhen the visual has a mobile layout.definition/bookmarks/, with a file per bookmark andbookmarks.json.definition/report.jsonanddefinition/version.json. Thisreport.jsonsits insidedefinition. The legacy one sits at the root of the report folder.
Which one you have today
Microsoft Learn says PBIR is generally available and is the default report format. Fabric Git integration and the Fabric REST APIs export reports as PBIR.
Automatic conversion, and the backups it keeps
When you edit and save a PBIR-Legacy report, Power BI converts it to PBIR without asking.
Power BI Desktop
Power BI Desktop keeps a backup for 30 days, in
%USERPROFILE%\Microsoft\Power BI Desktop Store App\TempSaves\Backupsfor the Microsoft Store version, or%USERPROFILE%\AppData\Local\Microsoft\Power BI Desktop\TempSaves\Backupsfor the installer version.Power BI service
For a report converted in the Power BI service, the service keeps a PBIR-Legacy backup for 28 days. To restore it, open Report settings from the workspace and select Restore as PBIR-Legacy.
NoteTo keep a report in PBIR-Legacy, do not edit it in the service, or use a Power BI Desktop release from before September 2026.
Names and limits
- Each page, visual and bookmark starts with a 20-character identifier as its name, such as
90c2e07d8e84e7d5c026. - A name may contain only letters, digits, underscores and hyphens. After renaming a file or folder, restart Power BI Desktop.
- A report can have up to 1,000 pages, and a page up to 1,000 visuals. All report files together can be up to 300 MB. The Power BI service enforces these limits.
If a PBIR report will not open
Open the file the message names in VS Code and read its schema validation messages. Two messages you may see:
Check a project in your browser
The Power BI Report Doctor reads a PBIP folder or .zip and lists the file and line to fix. Nothing is uploaded.
Other guides
- What is a PBIP project, and what is TMDL?A Power BI project (PBIP) saves a report and its semantic model as plain text files in folders, instead of one
.pbixfile. - Power BI Desktop can't open a PBIPWhen Power BI Desktop refuses a project, the message usually names a file.
- PBIP and Git: what to commit and what to ignoreA PBIP project is plain text, so Git can track it.
Sources
- Microsoft Learn: Power BI Desktop project report folder. The file list, "PBIR format", "External changes to PBIR files", "Convert existing report to PBIR" and "PBIR considerations and limitations". Page dated 2026-09-29. Read 2026-10-04.