Have questions about COVID tests? Here's what to know about expiration dates, free testing and more

Both COVID cases and hospitalizations have climbed in recent weeks, leading to heightened concerns ahead of the usual cold and flu season.

But this time around, the director of the Center's for Disease Control and Prevention, insists "we're in a different place," explaining that widespread immunity - either from contracting COVID or getting vaccinated - has reassured public health officials, NBC News reported.

Still, with an uptick in cases, you might be wondering what to do if you or a family member happens to contract COVID-19. If it has been a while since you came down with COVID, it's understandable if you've questioned whether testing guidance has changed in recent months.

Furthermore, questions are possible too, like can you still use expired COVID tests? Here's everything you need to know, including what to do if you test positive, where you can get discounted or free COVID tests and more.

If you experience any symptoms associated with COVID, health officials recommend that you get tested as soon as possible. The following are a number of symptoms of the virus - but not all:

Called the "the gold standard" of COVID tests by the CDC, PCR tests are more likely to detect the virus than antigen tests. However, it may take up to three days to receive results, because samples must be taken to a laboratory. Antigen tests, meanwhile, are very accurate and reliable, and typically produce results in 15 to 30 minutes, according to the CDC. However, they're generally less likely to detect COVID than PCR tests --- especially if you're not showing symptoms.

If you're planning on taking just one test, a PCR might be your best option. If you take an antigen test and receive a negative result, the CDC recommends that you take another antigen test within 48 hours or undergo a PCR test to confirm your results.

Anyone who tests positive, according to the CDC, should stay home for at least 5 days and isolate from others in their home. If you must be around others, it's recommended that you wear a high-quality mask or respirator to protect those around you, according to health officials. If your symptoms are improving and you've been without a fever for at least 24 hours, you may end isolation after day 5. If you still have a fever, continue to isolate until you're fever-free for 24 hours.

If you happen to have COVID tests lying around, and you think they're expired -- they might not be. The Food and Drug Administration said on its website that tests' authorized expiration dates may go beyond the date printed on the box.

To see if the expiration date has been extended and how to find a new expiration date, the FDA suggests you check its list of Authorized At-Home OTC COVID-19 Tests. It's important to note that the FDA doesn't recommend using at-home COVID tests past their authorized expiration dates.

While you could previously order free COVID tests online through a government website, that's no longer the case. The COVIDtests.gov program, which distributed more than 755 million tests, stopped accepting orders on June 1.

However, free or discounted tests may still be available to those in need. Through its Increasing Community Access to Testing program, the CDC offers no-cost COVID-19 testing for uninsured individuals who are either symptomatic or have been exposed to COVID. Head here to find a testing site near you.

If you have insurance, it's likely you will be reimbursed or an in-network facility will provide a test at no cost. Additional information on the reimbursement process can be found on the Centers for Medicare and Medicaid Services website.

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Best free PDF reader (2023)

The best free PDF reader apps are perfect for viewing documents, collaborating online, and making changes to your PDF files without any subscription charges or one-off fees. 

Using your browser is the easiest way to read a PDF online, but options are usually limited. To do more with your documents, both online and offline, it’s worth investing time in the best PDF editors, the best free PDF editors, or dedicated PDF reader software. 

PDF readers are the ideal solution for casual users looking for easy-to-use apps and platforms. Better still, the very best free PDF readers come equipped with plenty of tools for power-users. So, look out for features like free PDF to Word converters that put you in control of your documents. 

With plenty of options out there, it can be a challenge identifying which free PDF reader is best for you. To help you find the right tool for your work, we’ve tested out a range of options, exploring everything from performance with large files to cross-platform compatibility and the best cloud storage integration.  

Best free PDF reader overall

Operating system: Windows, macOS

Multi-platform support

Handles large PDFs with ease

Tab view for multiple documents

Relatively large

Regular 'upgrade to Pro' ads

Some tools paywalled

Adobe Acrobat Reader DC is a free PDF reader software for Windows and Mac (with Android and iOS PDF reader apps available, too). And it's our top choice for best free PDF reader overall - although we found features one massive downside.

The top PDF viewer is designed with two purposes in mind: the first is to enable you to read and interact with PDF files (including adding annotations and even signing a document). 

The second is to convince you to upgrade to the paid version of the software (which, you’ve guessed it, has many more features, including the ability to create and edit PDF files).

If it wasn’t for the latter, Acrobat Reader would be a decent addition to your software library. It’s simple, easy to use, and comes with all the basic features you need to interact with PDF files. In our review, we reckoned that “Adobe Acrobat Reader DC is one of the best free PDF readers for anyone looking to view documents and manipulate them in some way.”

Sadly, the adware side of things is pretty much everywhere: you get ‘try now’ buttons, you’re offered to use powerful tools but later are asked to pony up some cash in order to actually use them, there’s even a ‘7-day trial’ button. If you can overlook this, it’s a great tool, but there are less obtrusive ones out there.

Read our full Adobe Acrobat Reader DC review

Best free PDF reader for wide platform support

Operating system: Windows, macOS, Linux, Android, iOS, Citrix

Allows you to create PDFs

Safe mode disables Javascript

Lightweight download

Some features require extensions

No OCR in free version

Foxit PDF Reader is more than just a free PDF reader – you can also create PDFs from scratch using this software. Integration with Microsoft Office allows you to easily turn documents you’re working on into PDFs. Or, you can scan a document or image and turn it into a PDF using Foxit Reader. The only thing that’s lacking in the free version is support for optical character recognition in scanned documents.

The software can be a little intimidating at first, but it’s relatively straightforward to navigate. That’s thanks to the fact that it uses the same ribbon-style menu as Microsoft Office. Tools for editing, signing, highlighting, and commenting are fairly easy to access. You can also merge or split PDFs by downloading free add-ons for the software. 

Another advantage to Foxit PDF Reader is that it offers security. There’s a Safe Reading mode that allows you to automatically disable Javascript embedded in downloaded PDFs.

Note that with the software's latest update, Foxit seems to have removed its PDF virtual printer driver, meaning you can no longer use the software to create PDFs.

Read our full Foxit PDF Reader review

Best free PDF reader that's fast and lightweight

Operating system: Windows, macOS, Linux

Small download size 

Loads extremely quickly

Can convert file types

No editing 

Not many features overall

Slim PDF is the best free PDF reader if you’re looking for something incredibly lightweight. The software download is really small, so is the perfect choice if you’re limited by hard drive space. Plus, that means that it’s able to open and load your documents faster than most of its competitors.

In our review, we called it "a sleek, minimalist PDF reader that only takes up a couple of megabytes on your hard drive." The downside to this small size is that Slim PDF is pretty basic. You can search and rotate documents, but that’s about it. 

And you have to go in knowing that. Slim PDF feather-light when it comes to features. If you're looking for a PDF editor, you won't find it here. Nor will you find tools for signing, filling, commenting, or highlighting, let alone multiple reading modes. This application reads PDFs plain and simple, cut and dry. 

While there is a menu option to convert a PDF to a Word document, doing this requires another software download. On the other hand, if your needs are similarly simple, the free PDF reader might just be the solution for you.

As a result, Slim PDF is truly just a PDF reader. It does a good job at this, though, leaving out the toolbars that can distract you from what you’re reading. If you frequently need to print PDFs, Slim PDF is one of the fastest and most simple options available.

Read our full Slim PDF review

Best free PDF reader that's feature-rich and packed with tools

Operating system: Windows, macOS

Touchscreen mode 

Plenty of annotation tools

Simple ribbon-style menu

No document signing or filling

Lacks advanced features found in Nitro Pro

The Nitro PDF Reader is another powerful free PDF reader in the vein of Foxit Reader and Adobe Acrobat DC. What makes this tool different is that it has a touchscreen mode that’s perfect if you’re working on a tablet. Touchscreen mode is especially nice for reading e-books, since you can flick the pages rather than scroll or click on a button.

While you can’t fill and sign PDFs with Nitro Reader - this is, after all, a pared back version of Nitro's Pro PDF editor, with no OCR or the ability to insert, remove,  and reorder pages) - it remains an excellent tool that will make everyday document-wrangling much easier.

The software does a nice job of enabling collaboration. You can annotate documents with underlining and strikethroughs in addition to highlighting. Comments are also supported, and they appear like sticky notes that are easy to spot as you read through a document. Helpfully, the software also allows you to convert between PDF and other document formats.

The software has a ribbon-style menu that will be familiar to Microsoft Office users. The menu is pretty easy to navigate since there aren’t all that many options available in Nitro Reader. Overall, we found the app to be a remarkably powerful free PDF reader that's packed with handy features you'll use time after time, all presented in a clear, adaptable interface.

Read our full Nitro PDF Reader review

Perfect if you need a free PDF reader with built-in OCR

Operating system: Windows

Optical character recognition

Text editing

Splits and extracts pages

Free version watermarks documents

PC-only

Rather than just being a free PDF reader, PDF-XChange Editor is also a free PDF editing program for Windows. The interface is a little more complex than some others but gives you easy access to plenty of helpful features. 

For most users, the main reason to use PDF-XChange Editor is the fact that it comes with inbuilt Optical Character Recognition (OCR). This means that if your original PDF document is a photocopy, PDF-XChange will still recognize the text and allow you to edit it. Also, PDF-XChange Editor lets you reformat text, and even convert it into fonts that aren’t already loaded on your computer. You can use this platform to merge or split individual PDF files. 

It's not the perfect free PDF reader, however. There is one big, unignorable disadvantage to using the app: it'll stamp a 'Created with PDF X-Change Editor' watermark on any PDF file you export. That disappears once you sign up to the Pro version, but it's still an issue that's going to put some people off. 

During our tests, we ultimately felt that while nothing stood out as incredible, there was also nothing that stood out as frustrating or annoying either. Under the right circumstances, it's a great product that has the ability to be your one and only PDF editor without any compromise.

Read our full PDF-XChange Editor review

Best free PDF reader for viewing only

Operating system: Web, Windows, Mac, iOS, Android

Cross-platform with apps for online, on Windows, Mac, iOS, and Android

Customer support is responsive

Plenty of editing tools

No sign-up to read PDFs

Full toolkit  requires subscription

Advanced tools may prove steeper learning curve than most

pdfFiller serves up a very simple free PDF reader experience. If your needs are basic, it’s quick and easy to upload your document and read it via your browser, or through the Windows, Mac, Android, and iOS apps. Not only is the PDF viewing process free, you won’t even need to sign up to read files. 

However, the platform is actually a full PDF editor, with plenty of additional features for document creation and editing like fillable forms, data redaction tools, online collaboration, digital signatures, and PDF converters. After a thorough review process, we ultimately felt that the platform is “a very versatile PDF document management system” for both personal and business use. 

When it comes to a straight PDF viewer, pdfFiller’s free service feels hobbled by the inability to do anything beyond reading files. You can tweak documents, but they’ll remain locked on your dashboard and unavailable as a PDF file. To really get the most from the service - and, to be fair, it offers a fair amount - you’ll need to subscribe to one of three monthly/annual subscription plans. Enterprise licensing is available, too, for teams of ten or more. 

Read our full pdfFiller review 

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When deciding which PDF reader is best to download and use, first consider which parts of your PDF file you need to change. If you’re just trying to add information to a form digitally, you’ll only need a basic editor that supports text insertion.

However, if you need to change the content of a PDF substantially, you’ll require a more powerful PDF software program that can make modifications to text or images already stored in the file. In some cases, especially if you want to change almost all the content of your file, it may be better to use a fully functioning PDF Editor or even the best PDF to Word converter instead.

A PDF reader is a program used to open, view, and print PDF (Portable Document Format) files. First introduced in the 1990s, PDF files are an excellent way to distribute documents containing text, images, and various other media types.

Many modern browsers can read PDF files, but the best free PDF readers still have their place. These dedicated programs give users more ways to interact with the file and offer greater control over how the document appears on the screen.

PDF files were designed to appear and function the same on any piece of hardware, so you'll find PDF readers for Android and other mobile devices too.

Deciding between a PDF editor and a PDF reader comes down to how you'll use the software. PDF readers are primarily designed to view documents - although many include online collaboration tools like commenting, highlighting, and annotating content. Altering a PDF file is often limited to small edits and manipulation. A PDF editor lets you design and create documents from scratch and make large changes. They almost always include powerful tools for power-users, like built-in OCR software and digital signature tools. 

If you keep your computer secure and download PDF software from the official source, you should be well-protected. But, as with many free tools, there are always risks. We've outlined five common reasons why free PDF editors may not be right for your organization - and the issues can be similar with free PDF readers. We've also looked at the main differences between paid-for vs free PDF editors. 

The best free PDF readers feature plenty of tools for viewing and sharing PDF files - however, they're often slightly more limited compared to paid-for counterparts. In many cases, they offer a taste of how the software works, with upgrades and subscriptions that add more tools. If you're only reading PDFs on your computer or mobile device, a browser will likely meet your needs. If you're frequently in and out of documents, making minor edits, and sharing files, a full PDF reader will likely suit you best. 

We test the best free PDF readers against the factors that users care about - from the interface and experience to performance and platform availability.

We also assess each tool against its use-case. Some want a lightweight reader, others need one packed with plenty of other PDF utilities for professional use - so we look at how well the free PDF readers deliver for their intended audience. 

We also ensure that free means free - no hidden charges. Any subscriptions, lifetime licenses, and upgrade fees must be clearly signposted. 

As part of our overall testing process, we've also reviewed and rated free and premium platform-specific PDF readers.

+ Best PDF readers for Windows+ Best PDF readers for Mac+ Best PDF readers for Android

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