Even though they’re over 25 years old, PDFs are still one of the main types of documents on the internet. Whether you’re trying to access your W-2, a contract, or an ebook, it’ll probably be a PDF.

But to view these important documents, you need to download a PDF reader on your computer.

There are hundreds of PDF readers, and some can cost you almost a thousand dollars per year, so we sifted through the internet to find the best free PDF readers you can download online.

Below, we curated 20 free PDF readers whose capabilities range from only viewing PDFs to creating, editing, and securing them.