Velin Georgiev Blog

How much is the SharePoint Online 25 TB limit per site collection

Would we hit storage hard limit quickly, if we go with one SharePoint site collection?

This is a typical question from stakeholders. The business does not understand site collection storage limits and more than that megabytes and terabytes and other disk drive capacity units. Surprisingly, this is normal and they have other non-computer system matters to dealt with. We as SharePoint consultants have to ensure them that they won't reach site collection limit any soon for their new SharePoint Intranet publishing portal.

Further business analysis is required for big enterprise portal

The above does not apply to all of course. If this would be SharePoint portal to a really big enterprise, then more detailed planning is required to identify the information flow and the content size that will be created on a weekly or some time basis. However the above covers more of the scenarios because I already have been involved in big intranet projects for pretty big companies like Maersk, Coca-Cola Hellenic, Prudential, Microfocus and the 25 TB limits were just ok for their SharePoint news portals.

News and Publishing site collection vs Collaboration site collection

There is the disclaimer, this post is about news portals and not collaboration portals or video and streaming portals. News portal traditionally has several authors that push news articles with some images attached and they usually do not upload big files within a SharePoint site collection. These are the traditional intranet news portals. If you plan to build publishing or learning system based on videos and streaming this post is not relevant to you. If you plan to build collaboration site for files and forms management, again this post is not relevant and further analysis have to be performed.

Let's look at office 365 document size statistics

What is the average size of an office document?

- Most web content is smaller than 200kB

- PowerPoint and PDF consume the most space

- Word documents are most frequent

- Official guidance on MSDN suggests that the average size office document is around 250 kB

Average Size of an office document is 321 kB.

Based on 100 different data sources spread across tens of millions of searchable items

What is the largest size of a 640x480 JPEG?

- Uncompressed 640x480 PNG 903 kB

- Uncompressed 640x480 JPG 876 kB


Based on that here is another assumption of myself.

- Uncompressed 2560x1920 PNG 3612 kB (Assumption)

- Uncompressed 2560x1920 JPG 3504 kB (Assumption)

Space for the SharePoint search index

- JPEG image in the index will typically be 3% of the image size

- PDF the average footprint is about 35%

- Word the average footprint is about 35% (Mine and pessimistic assumption)


If 25 TB in just Documents or Large images

Let's do some math with one large news article assumption…

Let's assume that one average news article would contain one ASPX page, 3 Large images and one document attachment:

- 1 ASPX pages = 1 x 280 kB

- 3 Large images = 3 x 3720 kB

- 1 Documents = 1 x 960.4 kB

One SharePoint news article to be of size = 12 400.4 kB (12.4 MB)

How many SharePoint news articles like that we can fit in 1 TB?

One large news article assumption…

1 TB ~ 80 642 news

25 TB ~ 2 016 063 news

How many news articles we can have in time based on the above 1 TB ~ 80 642 news?

When the authors publish 20 news per day

1 TB ~ 4032 working days

4032 / 260 ~ 15 years (approx. 260 working days instead of 365 full days)

When the authors publish 100 news per day

1 TB ~ 806.42 working days

806.42 / 260 ~ 3,1 years (approx. 260 working days instead of 365 full days)

Please note, I do not take into consideration Versioning, More indexes on lists, Shredded storage.


In the pessimistic scenario publishing portal will hit 1 TB on the 3rd year and 25TB after 15 years, if just used for publishing. My assumptions may be very subjective, but at least can give an idea of some sizes and can clearly answer the question "Would we hit storage hard limit quickly, if we go with one SharePoint site collection?". Well, the storage should just be OK for a publishing portal. As another suggestion, set SharePoint alert when storage reaches some size and monitor them on a regular basis.

The optimistic scenario is ~ 31 years for 1 TB

If we follow this article for the average web page size is 1246 KB and assume that this would be the average page for our publishing portal, then: When the authors publish 100 news per day

1 TB ~ 802 568 news

100 news per day

1 TB ~ 8025 working days

8025 / 260 ~ 30.86 years

How much is 25TB SharePoint site collection power point presentation

Storage for SharePoint Online site collections limit is 25 TB