FreeFileSync

Many years ago (and if you read my other reviews posted on dAppCDN) I had all kind of bad memories with how I lost my data. Viruses, HDD (hard drive failures) - like many users back then - I experienced them all.

The only "reliable" backups were actually the CDs and later the DVDs - if there was something so important then you would've made at least two copies and pray nothing bad happened.

Anyway, the first external drives were not necessarily bullet proof it just offered another way to store data (let's call it more comfortable) - and it was quite expensive in the first years. I recall when one my external drive failed and I lost three years of photos. Not backed up anywhere - because, as I said -it was more comfortable to drop files on an external HDD than to write them on CDs/DVDs.

So I learned my lesson - I bought several external drives but then my life became so complicated.

I started to copy folders between drives after that - but I kept forgetting which files I was updating - and the "Do you want to overwrite?" or "This file already exists" were so frustrating. Or I was editing the wrong version on the wrong drive, then I found the same folder copied several times etc. A total mess.

So, naturally, I started to look for a reliable backup program. That's how I discovered FreeFileSync. And I can say it changed how I handle backups forever although, I find myself checking if everything is there.

Description

FreeFileSync is a folder comparison and synchronisation software. You can use it to compare two folders and see exactly what is different, then sync everything with a single click. There is no cloud service, no subscription and the peace of mind that your data is not shared with a third-party company. It is a software that copies only what is changed between your folders.

The project was launched in 2008, it is open source and it is actively developed by a developer named Zenju.

FreeFileSync Features

Feature	Description
Visual comparison	You can see folders side by side with colour coding - red for deletions, green for new files, blue for updates
Two-way sync	You can make changes on both sides and FreeFileSync will merge them, detecting conflicts
Mirror backup	You can create exact copies - if you delete them from source, it deletes them from target
Versioning	You can keep old versions of deleted files in a separate folder with timestamps
RealTimeSync	You can set folders to watch and sync automatically when something will change
Batch jobs	You can save configurations and run them with a simple click or you can schedule them
Network support	You can sync with network shares, FTP, SFTP are supported and even other third-party services such as Google Drive
Move detection	You can rename files and FreeFileSync will move them instead of deleting or attempting to copy them
Multi-folder pairs	You can sync Documents to Drive :D and Photos to a NAS in a single operation
Filters	You can exclude temporary files, system folders and specific extensions
Parallel copying	You can transfer multiple files at once in order to reach a faster network speed
Locked files	You can copy files in use via Volume Shadow Copy on your Windows OS

What It's Like to Use

The interface is blazing fast, it will load up instantly. There is no splash screen, no loading bars. You will notice two panels - a left folder and a right folder.

You can drag folders in or browse to them. Then click on "Compare". In just a few seconds (even with hundreds of thousands of files), you can see the differences. Green "plus" shows up for new files. Red "minus" for deletions. Blue "arrows" is for the updates.

Please note: Each change will allow a preview before you start the sync process!

I will be honest - it looks functional rather than some crazy modern design. Maybe like something from a few years ago but I don't mind - I prioritze functionality over any design. I keep mentioning this in all reviews I post on dAppCDN and there are many great software titles that does the same: put functionality and reliability over design. Anyway, you understand everything in about two minutes. There are no hidden menus and no complicated settings that will make your life harder so thank you Zenju!

Back to the interface, the synchronisation modes are easy to understand. For example, the mirror makes the right identical to the left. Two-way keeps both sides updated. The update will only copy newer files. You pick what you actually need!

Moving on, setting up filters will take you seconds. Type *.tmp to skip temporary files. Add "\System Volume Information" to ignore Windows folders. Save it as a batch job and the next time all you have to do is to double-click the .ffs_batch file.

RealTimeSync is amazing. It will "watch/monitor" your folders in the background. Any change? Wait a few seconds (you can set the actual delay), and it will sync automatically. I use this to keep my backup drive current without thinking about it - especially for important stuff.

During the sync, you can see everything - the current file, the speed, remaining time and a graph showing you the= transfer rate. If a file fails (because it is locked or due to a restricted permission), FreeFileSync will continue with the rest and it will show you a summary. Of course, you can retry any failure or chose to skip it.

I got surprised when I realized that FreeFileSync can detect moved and renamed files. Instead of deleting from the old location and copying to the new one (which takes ages for certain large files), it just renames them on the target. Surprisingly, this works even with the FTP servers that don't track file IDs.

The software can also handle paths over 260 characters. It can preserves timestamps. It will copy NTFS permissions if needed. It will use binary comparison to verify files match exactly. You can even pause mid-sync then close the program and come back tomorrow and resume everything.

For those who use network drives, the parallel operations are again so great. Instead of a single file at a time, FreeFileSync can transfer multiple files at the same time or better said - simultaneously. I got surprised when my NAS backups went from almost three hours to less than 50 minutes.

Google Drive integration will work without installing Google's sync software. FreeFileSync will connect directly, buffers directory listings and transfer only what has changed. Google even granted high quotas for FreeFileSync users.

FreeFileSync Alternatives

Name	Free or Paid	The main difference
GoodSync	Paid ($30-40)	It has a more modern interface, it will offer built-in cloud services but there are some yearly fees
SyncThing	Free	It is a capable device-to-device sync tool but it does require some technical knowledge
Microsoft SyncToy	Free	It is a basic sync from Microsoft but the development has stopped back in 2021
Robocopy	Free	It is a powerful Command line tool but there is no visual interface
rsync	Free	The popular, original Unix tool but there is a command line only as far as I know

Final Thoughts

FreeFileSync is such a great app for my workflow. For example, I can sync my work laptop to my desktop any time I want to - let's say each evening. My photos can go to two backup drives automatically - after losing them a few times in the past this really makes me happy. Project files mirror to my NAS in real-time etc.

I repeat, the interface is not going to impress you much if you care about the look.

What is more important is that you need to understand mirror vs two-way. But once you set it up, FreeFileSync will work great. There are no subscription emails. No features locked behind paywalls. There is no data sent to third-party servers.

So, I would say this. If you still copy folders manually or your trust a single drive with your data, please stop!

Download FreeFileSync. Set up your first sync job. In less than five minutes, you will have a backup system that works.

Finally, if you find FreeFileSync useful please consider donating towards Zenju. Not only because it is a great, useful software but Zenju did a huge change back in 2010 and switched to a donation-only model which was such a courageous act. He could've made more money from misleading ads or accepting bundled installers but instead chose a high moral standard. So, again, please consider a donation!

FreeFileSync has saved more important data than you can imagine.

No release notes available