PDF files have been around for a long time and remain a hugely popular format for document sharing. But their file size can mount when they run many pages long or have heavy graphical elements, which can cause issues when trying to send them on.
To help you with that, we've rounded up some free tools that will help you compress a PDF and reduce its file size. You can use a downloadable program to achieve this, but you can also use an online service; we will explore both.
If you have your own free PDF compressor to recommend, please do share it in the comments.
1. Smallpdf
Platform: online
If you're looking for a quick and simple way to shrink your PDFs without needing to download anything, then Smallpdf is for you. This is an online service that is a breeze to use, offering a drag and drop interface and speedy compression. Not only can you access it from anywhere because it's online, but it's platform agnostic too.
Though fairly basic in its functionality, there are some neat extra features like the ability to import your file from Google Drive or Dropbox (and save it back to the cloud once you're done.) The only downside is that you're limited to compressing 2 PDF files an hour, unless you cough up $6/month.
Results of the compression varied, simply because the system is designed to reduce to 144dpi with no customization for anything else. For example, a 5.72 MB file went down to 3.17 MB, while a 96.98 MB went down to 87.12 MB. Nevertheless, if you're just trying to get the file size down without a specific MB target, Smallpdf is great.
2. iLovePDF
Platform: online
Another online service, and one that offers a bit more finesse when it comes to the file size, is iLovePDF. You can upload a file from your system, Google Drive, or Dropbox, then select one of three compression levels. The more compression you apply, the lower the contents of the PDF will become. However, this also means that you'll have a smaller file size.
Using the same 97 MB file from before and applying extreme compression, I was able to get it down to 50.29 MB, a reduction of close to half the original size. All the files I uploaded were processed quickly and I didn't run into any limits in regards to how many times I could use the service. Note that you can only upload a single file at a time.
Files delete themselves automatically after about an hour, though there's likely no reason that'd be a problem since you can just save the file back out to your system or the cloud. If you're looking for greater control in an online PDF compressor, along with some impressive file size reductions, check out iLovePDF.
3. Free PDF Compressor
Platform: Windows
This lightweight compressor does what it says on the tin. Though it isn't updated regularly, it works on Windows 10 and previous operating systems just fine. If the online tools are too basic for you, then this doesn't offer a whole lot more, but it does mean you won't have to rely on an Internet connection. If you're looking for a deeper feature list, then you often have to turn to paid programs.
Nevertheless, Free PDF Compressor does give you the ability to use one of five presets to shrink your file down. Simply select your compression setting, point to the file path where the PDF lives on your system, where it should output, then you're good to go.
The low resolution option is highly effective; though it obviously harms quality a fair bit, it impressively shrunk down a 50 MB file to 15 MB. And it works quickly too when processing, though I did find it to be occasionally sluggish when files entered the three digit file sizes.
4. PDF Compressor
Platform: Windows
If none of these tools are what you need, try checking out PDF Compressor. It's very handy because it allows you to batch compress, selecting from files and entire folders. Though the program hasn't been updated for three years now, it'll still runs as it should on Windows 10.
The only caveat to PDF Compressor is that sometimes it can be really ineffective in its compression. A 50 MB PDF only lost just over 1.5 MB of its file size, which isn't much to write home about. There are compression settings, but only in the paid version. But the program is included here because it can be effective, it processes very quickly, and the batch feature isn't too be sniffed at.
Other File Size Reduction Methods
Compressing the PDF and altering its quality is one way to reduce the file size, but it's not the only way. For example, you could remove pages or make use of an archive format like ZIP. For tips and advice on this and more, check out our guide on how to reduce PDF file size.
On the other hand, if you're after some more tools for compression or want those that perhaps offer more than just PDF compression, like a full-on image viewer, our four tools for PDF compression article is available.
Do you often need to shrink your PDFs down? What free tool do you use to achieve this?
Image Credit: hand squeezing by Alexandru Nika via Shutterstock