The average Microsoft 365 tenant stores hundreds of gigabytes in files no one has opened in over a year. Most of it hides in corners: deep document libraries, forgotten project sites, and five years of version history on a single 200 MB CAD file. This guide covers five methods for locating large files across SharePoint Online, from the admin center down to scripted queries, so you can find the waste before it becomes a quota crisis.
What counts as a "large file" in SharePoint Online?
A large file is any item whose size, multiplied by its version count, meaningfully dents a site's quota. A single 2 GB video with no versioning is easy to spot. Harder to catch: a 15 MB PowerPoint presentation with 400 versions consuming 6 GB for a single document. The methods below surface both patterns: individual oversized items and libraries where version bloat has quietly overtaken the current file sizes.
SharePoint Online's base tenant storage is 1 TB plus 10 GB per licence purchased. Unmanaged versioning and forgotten large files are the two fastest ways to exhaust that allocation without realising it.
Method 1: Find large files with the SharePoint admin center
The SharePoint admin center gives you a per-site-collection view of storage consumption. It is the fastest starting point when you do not know which sites are the problem.
- Sign in to the Microsoft 365 admin center and open SharePoint admin center.
- Go to Sites > Active sites.
- Click the Storage used column header to sort descending. The heaviest site collections rise to the top.
- Export the full list to CSV using the download icon if you need to analyse it in Excel or share it with the team.
This gives you the ranking of sites by total storage. It does not tell you which specific files or libraries inside those sites are responsible. That requires the next two methods.
Method 2: Site storage metrics page
Once you know which site is the heaviest, drill into its per-library breakdown:
- Open the SharePoint site in question.
- Go to Site settings > Storage metrics (listed under Site Collection Administration in the settings menu).
- The page shows a folder tree with storage totals at each level. Navigate into the document libraries consuming the most quota.
- Click a library to see per-folder detail, then navigate to individual files.
Each file's Total Size on this page includes all of its stored versions, while the File Size column in the library itself shows only the current version. A file whose total here is many times its size in the library is a version-bloat flag worth investigating.
Method 3: Excel storage reports with Report Master
ShareMaster's Report Master has two storage reports that go down to the file. Site Storage Metric covers every document library on one site. Tenant Storage Metric covers every unlocked site in the tenant in one run and needs the SharePoint Administrator role.
What the reports include
- Report Summary: one row per library with its storage in GB, both with and without old versions, and what trimming them would give back
- The largest files: site, file name and path, size with versions, size of the current copy, and the saving a trim would make
- On Site Storage Metric only, a detail sheet for each library where every file is followed by its individual versions and their sizes
The largest-files sheet is already ranked by size including versions, so your top offenders are at the top of the sheet, and on the tenant report that ranking spans every site. Sort it by the amount saved if trimmed to separate files that are simply big from files whose history is the problem. This is the fastest path from "I know the site is heavy" to "I know exactly which files to address."
Files with hundreds of versions on a 50 MB document are exactly the kind of item that silently fills a quota over months, and the per-version rows on the site report show how fast each one is growing. If you also need created-by and modified-by details for every file, the Export File List report writes those with the current file size.
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Method 4: Version history audit with the Version Trimmer
Version bloat is a distinct problem from single large files. A library full of Word documents averaging 3 MB each sounds modest until unmanaged versioning has run for five years and each document carries 300 versions.
Using Space Master's Version Trimmer
ShareMaster's Version Trimmer works on the libraries you pick on a site, and the Bulk Version Trimmer on the sites you pick across the tenant. You set a keep policy (for example, keep the 10 most recent versions, or only delete versions older than a date you choose) and run it in report mode first: nothing is deleted, and the report lists each file with the number of versions the policy would remove and the space that would free.
This pairs well with the Report Master storage reports: use them to rank the heaviest libraries, then use the Version Trimmer to calculate and reclaim version storage within those libraries without deleting the live files themselves. The trimmer deletes versions rather than sending them to the recycle bin, which is why the report run comes first.
See also: How to trim SharePoint Online version history for a step-by-step walkthrough of the trimming process.
Method 5: PnP PowerShell (scripted approach)
When a GUI tool is not available, PnP PowerShell can pull file sizes from a single library. It works, but it requires scripting knowledge, a PnP app registration in Entra ID, and care around the list view threshold.
- Connect:
Connect-PnPOnline -Url https://<tenant>.sharepoint.com/sites/<site> -Interactive - Pull items:
Get-PnPListItem -List "Documents" -Fields "FileLeafRef","File_x0020_Size","Modified" - Export to CSV, open in Excel, and sort by
File_x0020_Size.
Limitations to be aware of: the File_x0020_Size field returns the current file size only. Version storage is not exposed through that field; you need a separate Get-PnPFileVersion loop per file to total it, which becomes slow and throttle-prone across a large library. Across a tenant with many sites, this script can run for hours and will hit Microsoft 365 throttling limits without a retry mechanism.
For occasional one-library checks, PowerShell is adequate. For tenant-wide or repeated audits, Report Master is faster and avoids the scripting overhead entirely.
Frequently Asked Questions
What is the maximum file size in SharePoint Online?
250 GB per file. In practice the bigger concern is volume: thousands of medium-sized files accumulating years of version history contribute far more to quota overruns than any single large upload.
Do file versions count against SharePoint storage quota?
Yes. Every stored version counts against your storage quota at its full size, and that applies to Office documents as much as to PDFs, images and video. A 15 MB presentation with 400 versions accounts for about 6 GB, which is why heavily edited large files are the first place to look.
Does the SharePoint admin center show file-level storage?
No. The admin center shows storage only at the site collection level. File-level detail requires the per-site Storage Metrics page, a Report Master export, or a PnP PowerShell query against individual libraries.
How can I find large files across multiple SharePoint sites at once?
The native admin center stops at the site level. For cross-site file analysis, run Report Master's Tenant Storage Metric report, which reads every unlocked site and writes one workbook listing the largest files across the tenant. The Bulk Version Trimming Report then shows what a version trim would free on the sites you pick, in a single session.