While many virus scanners purport to be free online tools, in actuality only a few do not require software download and installation. To clear up any confusion, we’ve verified and ranked the top 5 REALLY FREE online and download-only virus scanners below.
If you suspected that your PC is infected with a virus and you haven’t yet installed AV software, an online virus scanner can provide a quick and free solution without the need to download anything to your computer. The advantage is that these web services run checks from a remote server, eliminating system lag on your PC, with no commitment to a paid subscription service required.
However, not all virus scanners are the same, and very few are actually cloud-based services. They also vary considerably regarding accuracy, customization and added features. Here’s what we managed to find out:
How We Tested
To find the best virus scanners, we used a machine with several known malware infections. Then we individually tested popular options, rating them according to:
- Ease of Use
- Online vs Download
- Ability to Identify Infections
- Additional Features
The following ranked the highest on all of these factors!
1. ESET Scanner (Download Required)
The ESET scanner is a reduced version of the full ESET security suite. It still provided flawless accuracy when identifying the infections. It was even able to name and locate every suspicious file. Although the scan took 30 minutes, which is longer than other options, it thoroughly explored the operating memory, auto-start locations, and local drives.
It also lets you delete or quarantine the infections, which is not an option with some virus scanners. The major drawback? It’s only available on 16-bit and 32-bit Windows systems; if you use a different operating system, you’ll have to look elsewhere.
- Scans entire computer
- 100% accuracy rate
- Includes anti-stealth technology (anti-rootkit)
- Scan customization available
- Comprehensive report available
- Downloadable add-on required
- Only available on Windows
- Full scan takes 30 minutes
I was disappointed that a downloaded-client is required, but this seems to be a common feature of most virus scanners. Very few work directly from your browser. However, it’s clear that the ESET scanner is a high-quality service. The amount of customization is notable; you can specify which features run and set automatic scans. I was particularly impressed with the anti-rootkit option, as it requires more sophisticated technology.
ESET Scanner offers a more in-depth virus scan than many others. Although it took longer than some, the detail of the anti-virus check and the results were worth it. Even without the option to delete/quarantine, it would have been easy to locate and delete the infected files manually.
The scanner is available for one-off events, but you can opt into a 30-day free trial of ESET’s full security suite. This package offers continuous, real-time protection without having to commit to a subscription or payment.
2. F-Secure Scanner (Download Required)
F-Secure is a Finnish cybersecurity company that offers a range of free online tools. Their download-required virus scanner is sleek and simple and effective. When tested, it removed the majority of malware on our system. The whole process was impressively quick for a download service, taking less than a minute. Once identified, you can see information about the infected files, with internet links for more details.
The client can also successfully remove the malware it finds via a system restart. While very user-friendly, it’s currently only available for Windows, but the company offers a free trial of their F-Secure Safe software for Mac users.
- Removes infected files
- 70% accuracy rate
- Takes < 1 minute
- Simple user interface
- Regularly updated for new threats
- Only available on Windows
- No Cloud-based scanner
- No custom scan options
- System-restart required
F -Secure virus scanner is definitely near the top of the pack. Though it requires a downloadable add-on, it takes up minimal memory. You can share your results with the company to help keep their threat database up-to-date. Not only does this ensure high-quality detection, but it also creates a community vibe. You don’t have to worry about privacy, as all results are anonymous.
The speed of the scan was another selling point; so was the fact you can actually remove the threat! F-Secure allow users to scan and delete infections for no extra cost. Although restarting the device was a slight inconvenience, a surprising number of other scanners don’t offer disinfection at all.
Overall, F-Secure scanner is impressive as a fully-rounded malware detection tool. It didn’t manage to detect every threat but it still performed well in all areas.
3. BitDefender Virus Scanner (Download Required)
BitDefender Virus Scanner is a low-usage app that’s part of BitDefender’s free toolbox. You can use it to perform a quick scan of your device’s critical areas, do a full system check, or target a custom location. We chose the first option and it completed the scan in less than one minute. It managed to identify that the computer was infected but didn’t find all the threats. We were able to quarantine the files but had to change user privileges to be able to disinfect. Overall, the scanner was generally effective but overly complex in some areas.
- Available on Explorer, Firefox, and Chrome
- Takes < 1 minute
- Adware removal tool also available
- Identifies malware fast
- Fastest option available
- No detailed results
- Some reports of interference with other apps
- Limited accuracy
The BitDefender Virus Scanner was by far the most complicated client to use. I liked how it listed each found threat, the ‘action taken,’ and a route to manually find the file. However, after locating the infections, it wasn’t clear how to delete them. Plus, the interface itself isn’t very attractive.
Once I finally managed to find my way into the settings, it was easier to see how everything worked. The scanner can be set-up to automatically disinfect or quarantine a file, if it’s capable. It wasn’t able to detect all of the known malware on the computer, which was clearly an issue, but was capable of removing common threats.
I also tried out the adware removal tool but was disappointed that it only worked for two adware types. In summary, the BitDefender Virus Scanner can get the job done, but only with some hassle and inaccuracy.
4. Norton Security Scan
Norton is a trusted name in cybersecurity, offering high-quality antivirus protection for nearly 30 years. Their security scan tool is a free online option that provides a quick scan of your entire system. When tested, it identified 70% of malware, alongside many suspicious cookies or apps that required updating. While its results were broader than most, the main downside is you aren’t able to remove the infections. Instead, you’re redirected to purchase Norton’s full antivirus software. The client also doesn’t disclose the names and locations of the infections, so you can’t even remove them manually. However, if you just want to check if you have malware, then Norton Security Scan is ideal.
- Full system-scan
- Suspicious cookies scan
- Identifies system vulnerability
- Premium detection quality
- Trusted brand
- Can’t erase infections
- Only available on Windows
- Advert for full software
Most well-known security companies now offer online scanners as a promotional device so the fact it couldn’t disinfect my system didn’t come as much of a surprise. However, removing the infection is arguably the most important part of antivirus protection.
Despite this, the actual detection rate is pretty impressive. Instead of just highlighting malware, it explores numerous elements of your device to uncover any potential security threats. If you already have an antivirus running, Norton Security Scanner is ideal to perform instant checks, instead of having to wait for a full system scan. Then, if you find an infection, you can switch to your installed software.
The security scanner isn’t compatible with Mac, but Apple users have the option to try any other Norton antivirus app without financial commitment or credit card information.
5. Bullguard Virus Scan (Download Required)
Cybersecurity giant Bullguard used to offer a dedicated online virus checker, however, they recently updated their system so users can now download a free trial of their premium security packages. These free apps provide fewer features, so are less memory-heavy for your computer. They can also be accessed via any browser, offering higher compatibility than other options. Unfortunately, it does require significant set-up time. Plus, no instant scan setting exists; you have to select critical areas in a custom scan.
- Available on most browsers
- Several options available
- Premium quality
- Available for 60 days
- No dedicated online scanner
- Long installation process
It was surprising that Bullguard removed the online scanning tool from their site. However, their free trial options are still remarkably quick and convenient to use. When installing, I wasn’t impressed by the time it took. Not only did I have to go through a set-up process, but I also had to create an account.
Although the client is well-designed, it doesn’t offer an auto-quick scan. To only search the critical regions, I had to create a custom scan and choose them manually. Nevertheless, the results were promising. It found most of the malware. I didn’t expect anything less, as the app is just a smaller version of their premium antivirus engines.
While I wouldn’t recommend the Bullguard virus scan as my first choice, it did successfully achieve its goals eventually.
Paid Antivirus Vs. Free Online Scanner
Online virus scanners can be used to identify threats quickly. However, we discovered that few cloud-based services exist, and in any case, they can never replace a full security suite. Most only offer an overview of the infection, and some don’t even have the power to remove it. If you want to ensure that your device and files are safe, we recommend installing a highly-rated, premium antivirus.
On the other hand, if you’re in a hurry or want an alternative perspective on a threat, free online scanners are the ideal choice. They’re light on memory usage, simple to install, and offer nearly-instant results. Just be sure you use more comprehensive security software to perform a more detailed scan when you have the chance.