How can I check if a file has a virus?

Viruses can be dangerous to the health of your computer. They can delete important files, steal personal information, or perform other malicious tasks. Like a human virus, a computer virus is capable of replicating itself and infecting other hosts. Given the destructive nature of viruses, it is important to understand how to best recognize and protect your computer against them.

Checking for Viruses

The best way to determine if a file has a virus is to scan your computer using antivirus software.

As Internet usage continues to grow, so does the presence of viruses and other malware. Fortunately, there are several antivirus programs available that recognize, quarantine, and eliminate viruses. These programs include a list of "virus definitions," which are signatures or codes used to recognize viral patterns in files. When an antivirus program scans a file, it can recognize a virus, warn the user, and quarantine the file for remedial action.

Below are examples of common antivirus programs for Windows:

Using Antivirus Programs

When using antivirus software, it is important to make sure your program has the latest virus definitions. Fortunately, most antivirus programs have an auto-update feature that you can set to run on a periodic basis, such as once per day or once per week. By using auto-update, your antivirus software will automatically download the latest virus definitions and include them when scanning your files.

If you want to check an individual file or folder for a virus, you can use your program's Manual Scan option. Most antivirus programs allow you to perform a full system scan or a localized scan of an individual file or folder. After scanning, the software usually provides a report with the scan date, file status, virus type (if one was found), and any remedial actions taken to handle the virus.


If you use Windows, it is especially important to have at least one antivirus program installed on your computer. macOS and Linux systems are less likely to become infected by viruses, but they are not immune to malware. Therefore, installing an antivirus or Internet security program on Mac and Linux computers can still help prevent unwanted software. Regardless of what platform you use, the best way to check your files for viruses is to scan your system with an antivirus program.