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TreeSize Professionalv7.1The powerful disk space management software

CompatibleWithWindows10 CompatibleWithWindows8 CompatibleWithWindows7



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More than 87,000 customers trust TreeSize. Many companies buy larger license packages enabling a greater number of users to access TreeSize at once. International corporations often use site-wide licenses or countrywide licenses - or simply request a world wide license. Our customer base continues to grow: With more than 1.5 million downloads per year from our servers alone our TreeSize product family wins over new users on a daily basis.

Thank you for the ongoing support for TreeSize.
I'm in independent consultant and on many occasions I was able to wow my customer just by using your tool. The duplicate file finder and the size changed over time are killing features for me.
Just yesterday I was able to demonstrate that a certain action of just manually updating a set of excel files would be a near impossible task since I was able to show them in less than 10 min that they had over 20.000 excels hidden in their networkshare.

The simplicity and speed is just awsome!

Manfred De Jong Consultancy

Very glad I bought the software yesterday!
I've seen my software company's support staff use Treesize.

I'm personally always pretty hesitant about purchasing software. But after trying out the trial... MAN!
It's night and day difference when compared to Windirstat.

The speed difference alone is incredible!

Thibault Molleman, Molleman De Coster BVBA

I've just tried a scan on a large bucket and it reported the results far quicker than I can get the results directly from the aws console!! Great work!! Amazing.

I remain super impressed with your work, thanks loads.

Charlie Daffarn, Omnicom Group IT | paige

TreeSize Professional from JAM Software is the most powerful program I’ve seen for analyzing how disk space is being used. Just load the program and specify the areas you want to scan. These can be one or more local partitions or paths, or partitions or paths on networked computers. Hit the Scan button and wait a while. But you don’t have to wait long! TreeSize is lightning quick. My local hard drive, which is partitioned as a main C: partition and a supplementary D: partition, has almost 450,000 files using 665 GB. The scan completed in 37 seconds!

Chris Taylor, President and System Administrator, Ottawa PC Users' Group

I LOVE the product and we use it daily for not only reporting but for administering our CIFS environment. *Honestly I'm probably doing more with the product than you intended but it has been a life-saver for my department.

Shelly Birkla, Storage Services, University of Notre Dame

TreeSize Professional is an outstanding product and was given the 'Very Good' award by its users.


Michael Ganss,

I LOVE this software! I will totally be recommending it to my clients.

Joyelle K. Jolie, Trainer and Tech Professional at SparQ Corporate Training

Yesterday I discovered TreeSize and downloaded a trial version. Kudos to the developers! You have done an incredible job with this program. Your team is remarkable. Incredibly perfect software! The straightforward clean design and functionality is absolutely amazing. I am an IT Director and will recommend this product to anyone that I think might find it very useful. It is always refreshing to experience clean, precise and intelligent software that truly makes life easier by saving valuable time.

M. Dogget, IT Director

This works like a charm. I was able to replace two software applications (Easy Duplicate Finder and SpaceWatch) with your current TreeSize Pro version.

G. Cota, Technical Service Specialist

Thank you, JAM Software, for dreaming up this application. It helps me manage local and NAS Storage more efficiently.

Kevin Tran - CT Corporation, A Wolters Kluwer Company

TreeSize is a great tool. It comes in three versions which you can compare on their website - Freeware, and two paid versions. [...]
TreeSize turned out to be just the solution I needed. If you keep running out of disk space and you have exhausted all the common disk clean up routines, give TreeSize a try.


Andre Da Costa,

This program has been TREMENDOUSLY useful to me. In particular, apart from figuring out what's going on in my own machine, it is GREAT for examining my LINUX file systems that I have mounted over Samba.

David Jameson

I have been using TreeSize Pro to keep an eye on what is taking up all our server space. I just found the feature to compare a previous scan result to an updated one. Wow. You have made my searching process so much simpler! Thank you! I continue to be impressed with your product!

Ryan Reif

You folks are the best... thank you so much for the quick reply and the easy resolution!
Very best regards, and thanks for developing products that are so easy to use and so powerful at the same time.

Dr. Tim Bremner, Vice-President of Advanced Engineering & Materials Technology, Hoerbiger Corporation of America, Inc.

Your software has enabled me to successfully identify and delete 199 '.data' files that had occupied 97% of my hard disk. WinDirStat had merely reported them as 'Unknown' and Folder Sizes identified them but did not allow me to delete them. So, although your product was (for me) quite expensive, it was money very well spent. Thank you very much! I will not hesitate to recommend it to everyone.

John Barker

I've looked through the revision history and noted the improvements you've made. You are to be commended for such an excellent product. This is just an excellent product. I don't know what else I can say other than it's superb. And I haven't yet begun to look at all the new features.

Harry Parker

Wondering where all your disk space went? Care to see how you're using your disk space and which folders take up the most space? You can easily do that with the powerful and flexible application TreeSize Professional. Any user who cares about efficiently using disk space is well advised to get this hard disk space manager.

George Norman,

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