Compress PDF Files Online for Free

Easily reduce the size of your PDF by using our online tool. It’s absolutely free and easy-to-use.
Drag & Drop the File Here
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How it works

Upload your PDF

It only takes a minute to compress your PDF file. Click the Choose file button and select the PDF from your computer. You can also drag and drop the document you’ve chosen into the box above.

Compress your Document

When you’ve finished uploading your document, click Compress and get your file size reduced in seconds. It’s simple as that. You can delete your PDF and upload a new one before you click the Compress button.

Absolutely Free

While most file compression software requires payment, AltoCompressPDF is absolutely free. There is no need to buy additional products. AltoCompressPDF will reduce the size of your PDF at no cost.

Encrypted file compression

Keeping your personal information safe is a priority for us. AltoCompressPDF uses an encrypted connection that guarantees all files uploaded are protected from unauthorized access and loss. All files are deleted from our server after they’ve been compressed.

Compatibility with major platforms

Our compression tool is compatible with all major operating systems like iOS, Linux and Windows. All you need to start using AltoCompressPDF is an internet-connected device. This means that you can shrink PDF on-the-go.

Converting files in the cloud

Even if your device's storage space is full, AltoCompressPDF will still operate. Our tool works in the cloud so you can shrink the size of your PDF whenever you need to.

How Do Users Rate AltoCompress?

Our service faciliates the work of over two million people converting PDF documents online every year.


We’ve all been there. You’re trying to send a PDF document via email and suddenly a pop-up tells you that the file size is too large to be sent. Or you’d like to save a PDF with images to your device but fail because there isn’t enough space on your device for such a big file.

Rather than wasting time trying to reduce your file size with costly software, choose AltoCompressPDF This is an online service that will reduce the size of your PDF in a matter of minutes - at no cost. Using AltoCompressPDF is simple and won’t take up much of your time.

How It Works

  • Start by selecting the PDF document you’d like to compress. You can do it either by dragging and dropping your PDF into the page or by choosing the file you need from your computer.
  • Make sure you have chosen the right PDF to be compressed. At this stage you can preview your PDF. AltoCompressPDF allows you to delete a PDF and upload a different file before you proceed to reducing its size.

AltoCompressPDF is the right choice for those who’d like to quickly and easily reduce the size of PDF document without being tied to their computer. AltoCompressPDF is a free, web-based solution that will help you get your PDF compressed on the spot. Besides speed, convenience and quality, AltoCompressPDF also offers industry-leading encryption to protect your document when it is being compressed. Try our tool today.