Security is an important concept in the modern world. Anywhere we go, we want to feel safe and secure. And that’s totally understandable. But what about the digital world? I think everyone should take preventions when using an electronic device (PC / smartphone / tablet …), especially one that works using an internet connection.

Why is this the case? I think you already know the answer. There are lots of threats online: viruses, malware, hackers and others. You should somehow protect yourself and your data from them. What’s the best and most popular way for doing this? An Antivirus Software.
There are many possibilities to install on your PC. Most people say that a premium (paid) software is your best bet for a secure computer. Is that really true? Mostly, something that you pay for is better than its free counterpart. But when we’re talking about a good antivirus software, things are a bit different.
Many developers and companies offer free versions of their programs. Yes, there are some limits to these versions, but most of them can protect you from the usual threats you might come across while browsing online or downloading something.
Another possibility would be to look for an antivirus that is open source. This means that the source code of the program is open for anyone to make a change. Of course, you will (if you want to) change the copy that was installed on your PC. These community developed programs are getting better by the day. You shouldn’t disregard these options, just because they’re free to use.
In this article I’ll walk you through more than 10 different antivirus software, that is ether free to use (has a free version) or is entirely open source. I’m sure you’ll find a candidate that will cover all your needs. Let’s jump in!
1. Immunet
Immunet is an entirely open source software developed to protect your PC from any online threat. This software utilizes cloud computing and community-based technology, to ensure the security of your PC while online.
It was developed to work flawlessly with any computer that uses Windows as its operating system. If your PC isn’t very new, or has older specs, you can still run this antivirus. For Windows 10 (latest version) all it needs is a 1 GHz or faster processor, 1 Gb or RAM (32bit operating system) or 2Gb for a 64bit system, and 850Mb available disk space.
But what will you get if you choose to install it? I’ll tell you right now. For start, it has a feature that any antivirus software should have: detection and removal of unwanted software or data (viruses, malware, spyware, bots, worms, trojans and keyloggers).
Something interesting about it, is the fact that you can use it to supplement your existing antivirus software. This basically means that your main antivirus will work together with Immunet to protect your computer. But you should know that Immunet is good to use on its own too. It can do pretty much everything your other software might do.
If Immunet detects a virus, you can choose to put the infected files in quarantine or remove them all at once. But putting them in quarantine can be a big help. There’s a chance the infected file is something you need, so you can’t just delete it. In this case, putting the file in quarantine, will allow you to remove only the virus without deleting any important data. But doing this, might require an IT professional. Still, a great option to have.
I mentioned the Immunet is an open source antivirus developed and maintained by its community. This is the other pro if you choose to go with it: the community.
Immunet’s community consists of more than 2 million members (and still growing). This can be a real asset for you. Why? Because a bigger community means a higher chance to find answers for possible problems. No matter how ‘’perfect’’ a software is, there will always be issues to be solved.
This is where the community comes into the picture. If you stumble upon a problem that you don’t know how to solve, the community is the best place to start looking for an answer. There are many forums online talking about Immunet. Just sign up to some of them, and start talking.
2. Bitdefender Free Version
The free version of Bitdefender is a lightweight and simple antivirus software. It is an award-winning software available for any user. This free verion leaves out some features that most programs have, but for a good reason. Because of doing this, Bitdefender Free is superfast and efficient at protecting your PC from any threat.
Basically, the main goal of this software is to protect your PC and shield it from online and other types (USB drives, Hard drives etc) of viruses and malware. Is it achieving this goal? Yes, it really does. We can safely say that it’s protecting your PC even better than many other paid programs.
To make sure your computer is secure, Bitdefender is scanning it in real time to find any anomaly. It’s looking for weird behavior between your installed programs. When it finds a file that is possibly infected, it will upload it to the cloud for analysis.
Now let’s list some of the available features with the free version:
- Improved Intelligent Antivirus – Scan and protect in real time
- Advanced Threat Defense – This looks for unusual behavior to assure security
- Web Attack Prevention – Preventing you from ever landing on a harmful website
- Anti-Phishing
- Anti-Fraud – Prevents fraud when you shop online (or banking and browsing)
- Automatic Updates – The software will be updated regularly, once a new version was released (without affecting your computer)
When you’re looking for a good antivirus program, you should consider one that doesn’t impact your PC in a bad way. Luckily, a great aspect about Bitdefender is the fact that it isn’t using many resources to achieve security. Many people who tested the software have reported that it has minimal influence on your computer’s performance. This is great news for anyone and a big plus for Bitdefender.
Something interesting about this program though, is that you don’t have the possibility to do quick scans of your PC. In fact, you don’t need them if you’re using this software. Why is that? Well, the first full scan of your system will be running when you first set up Bitdefender. This scan takes up about 1,5/2 hours.
Once this scan is done, and Bitdefender learns what files are safe and do not need to be tested every time, you can run full system scans anytime you want. And every such scan takes about 5/7 minutes. Yes, only 5 minutes. That is exactly why quick scanning isn’t an option. The full scan is actually better, and it lasts only minutes.
3. Comodo Antivirus Free
This software is available for Windows users running Windows 7 / 8 and 10. Comodo can protect you PC from any kind of virus, malware, trojan, rootkit, adware and spyware. What features does Comodo give you?
- Default Deny Approach: This is basically the first line of defense on your computer. It scans any new file that wants to enter your system. Once it’s proven to be harmless, you can copy or install it without a doubt.
- Containment: This feature is a backup for the first one. It will put your files in a separate environment, where they are tested to be sure you can use them.
- Host Intrusion Prevention System: This is pretty self-explanatory. It monitors your PC and prevents malicious attack from different sources.
- Virus Scope: Used for local PC analysis.
- Whitelisting: This option lets you mark specific files, so you know they are safe. Default access will be granted to such files.
- And Others!
For a free antivirus tool to be this powerful and versatile is quite unusual. If you want a software that can do many things, Comodo could be a good choice.
Alongside the already mentioned features, Comodo can do something interesting, but very helpful. It’s called Rating Scan. What is this? Well, obviously this option will scan your PC. But there’s something else to it as well.
Rating Scan will go through all the running processes and the most frequently infected areas. Once it finishes, you will have displayed a report based on the reputation of each file or process it found. Why is this helpful? Just think about!
Maybe you’re suspecting an infection, but you’re not sure where to look for it. In such a case, the Rating Scan could be the way to go. It will point out the files that aren’t clearly a risk, but they have an unusual behavior. Based on this report, you can start looking in the right direction, thus reducing the time needed to find the issue.
A pro about this program is the user interface. It was created to be appealing for any user. It doesn’t matter if you’re not a techy person, you can still use this software easily. But be aware that there are certain features that need a little bit more expertise. Though they are not necessarily needed for an average user.
4. Clamwin Free Antivirus
Clamwin is an open source software free to install on your computer. More than 600,000 people use it worldwide, every day. The installation is easy and fast for any user. It packs some nice features too:
- High rates of detection of viruses, malware and spyware
- Scheduled scanning
- Automatic updates using the latest virus database
- A standalone scanner
- Possibility to integrate into Windows Explorer
- Works alongside Microsoft Outlook. Scans emails for infected attachments.
You’re maybe thinking: ‘’But isn’t this software outdated?’’ Well, it’s not the most modern among the others, that’s true. But I wouldn’t call it outdated. As I already mentioned, it is being updated with the latest data from the virus database. This makes sure, that Clamwin can detect and eliminate even the most recent viruses.
5. Kaspersky Free
A well-known player among the alternatives, Kaspersky is a popular choice for lots of people (more than 400 million users globally). It’s a pretty simple antivirus, with not so many bonuses. Still, it’s got one of the fastest scanning engines out there.
All that’s included with the free version is of paramount importance for the software to work as well as it does. For instance, you get protection against dangerous websites and a superior scanner to ensure your protected against any online threat.
Kaspersky Free uses the same technology as its premium counterpart. This consists of 3 elements needed to make sure your data is secure on your local PC. The first defensive line is a file scanner that I already specified before. This will match your local items/files with known threats.
The second step is an analysis that searches for signs of weird behavior in your system. These could be associated with a malware attack. The third and final step it takes is the inspection of any new file that looks out of place, and sends updates to all the other users. Doing this, will prevent everyone else to get infected in the same way, or with the same files.
With Kaspersky being so efficient in handling threats, you may be thinking it must use up all your resources to obtain these results. If that’s what you’re thinking, you couldn’t be more wrong about it. It uses a moderate amount of system resources to give you this security. From many benchmark tests, it resulted that the software slows down the PC so little, that a normal user won’t even notice much.
What about its user interface? Kaspersky Free uses the same UI as the paid version. It’s a clean and easy to grasp display. When all is good and secure, everything will be colored green (of course). When yellow appears, you should know that there’s a new update and it’s waiting for installation. Red is obviously a bad sign. You might be under attack or some files could be infected. Take precautions and get rid of the problem.
6. Sophos Home Free
Sophos is a company developing security software for more than 30 years now. Most of its programs were made for enterprise usage, but these days, they make available the Home Free version of their antivirus program for personal use also. Is it any good? Let’s find out!
For start, let’s see how easy the set-up is. Well, I can safely say that anyone can set up this software. You just have to find the free version on their website. Once you got that, just download and install it. It will ask you to create an account with your email address, but this is something usual (most of the others ask for this as well). If you don’t want to receive offers from the company, just don’t tick that option. After all this, the program will set up everything it needs, without asking for your assistance.
Sophos isn’t the most lightweight program. Once the installation is completed and you check how your system is performing, you can see a considerable raise in the RAM usage. This depends on your personal PC, more or less. But the program uses more resources, than some of its rivals, nonetheless.
Now, I’ll talk a bit about the features you get with this free software. On one hand, the user interface is very nice. The company made it to be user friendly (like a lot). When you open up the program, the dashboard will pop up. Here you can see some status information, like when you had your last scan or your last update. There’s also a button to scan your computer and another one for managing your security. That’s pretty much it. It’s a simple dashboard with not too many features.
There are, other option available too, but only if you log into your account on their website. Using the Protection tab in your online account, you can enable or disable all sorts of modules: web protection, un-wanted program detection, real time protection and something called download reputation service. This last option will give all your downloaded files a score based on their content and the site they come from. This way, you can protect your computer from potentially unwanted downloads.
So, is Sophos good enough for your needs. Well, that’s totally up to you to decide. But as recent benchmarks pointed out, Sophos Free is very efficient at handling threats. For example, a recent test that was made for the Android system, resulted in a total success. In other words, Sophos was able to detect and neutralize every malware and threat that attacked the system. After all, that is the reason to have an antivirus installed. Check it out for yourself!
7. Avast Free Version
Avast was founded in 1988 and has grown into one of the biggest competitors against other antivirus software companies. With more than 430 million monthly users worldwide, it really is a popular choice among people. But does it live up to the hype? The short answer is: YES, it does. Why? I’ll tell you why, right below:
One of the biggest pros for choosing this software over others, is the multitude of feature and options it gives you. It certainly outperforms even some paid applications. But how? For start, it’s got a nice user interface, created to be simple for even non-techy persons. This is especially important considering the many options you have available for use. If the interface is too loaded with information and features, you might get confused and look for another software. Avast is good at avoiding this outcome. They made a dashboard that works easily for anyone.
The set-up is also handled easily. Something good about Avast’s set-up process is the custom installation. You can choose this option when you start the installation. It will allow you to decide between 14 different available modules to set up or not, according to your personal needs. Most antivirus programs won’t work if there’s another program running, doing the same thing (in this case, securing your computer). But Avast is different. You can set it up even if there’s another antivirus already running. Avast won’t be the main protection, but it lets you do scans and updates anytime. Of course, if you disable the other antivirus, Avast will take its place.
Let’s see what some of the features are and what are they accomplishing for you! To detect potential threats, you need to scan your PC. Avast is great at this. It comes with more possibilities to scan a computer than you may even need. For instance, you can do a whole system scan (this is good at first set up). If you want something faster, go for the quick scan option. Avast also comes with custom scan and it allows you to scan certain folders and files to your liking. Scheduled scans are also possible. For example, you can program Avast to scan your computer when you next boot it up.
Another useful feature is the web filtering tool. This is mostly handled by the browser add-on installed with the program. It will highlight dangerous links and websites for you to notice and avoid. A Wi-fi scanner is also included among your other options. This is a powerful tool to let you know who else is using your network. Software Updater is a small tool that lets you know if you have any outdated software on your computer so you can update them accordingly.
Are you a hardcore gamer? Or you just like to play something occasionally? Then Avast is a good choice either way. It includes a feature specifically created for when you play a game. If you turn it on, Avast will turn off all the notifications and it’s going to boost your gaming experience for a better performance. Who likes a lagging gameplay, right?
Finally, what can we say about the protection it gives you? According to most of the tests, it can stop pretty much any threat that could pop up. It scored well on different benchmarks, blocking 99,5% of the threats to your PC. It uses some resources to achieve this score, but not as much for you to notice any difference in the loading time for certain programs.
In conclusion, Avast Free is a great choice for those who need many options and a good protection from a free software. It’s highly customizable at set-up and it blocks almost ant malware, while boosting your gaming experience.
8. Avira Free Antivirus
Avira is a German company creating security software for personal and business use. The free software they provide is a good choice for personal use. Just like many of its competitors, Avira also uses a modern and fast engine to search and block potential threats. To protect you while browsing the web, it uses browser add-ons that work well with many programs (Opera, Firefox or Chrome).
Let’s talk about the set-up: differently from Avast, Avira doesn’t possess a custom installation option. But you don’t really need it. Why? Because Avira isn’t coming with as many features as Avast. So, you just have to download the software from the official website (which takes just 1 click) and then install it. It won’t ask you to create any account, you just accept the license and Avira gets installed in a few minutes.
Just like Avast, Avira is also well performing if you already have another antivirus on your PC. It’s not conflicting with other software, so if you somehow forgot to uninstall your old antivirus, that won’t be an issue.
Avira is quite big on disk when you finish installing it, about 800/900 Mb with all the files copied onto your computer. It’s good news though, that it’s not using a lot of your RAM, about 100/150 mb. So, it should run well even on older systems. Differences in loading times shouldn’t be noticed (almost at all).
You won’t have too many features available using this program, though custom and quick scanning is ready for use. Something interesting is the fact that you can create a scan of your own. This means that you can specify the drives and files it will scan. Doing this, you can leave out those things that need no scanning. You can set certain situations that need an Avira warning.
Avira has a very good protection at 99,7% stopped threats. If you need a program that is easy to handle, with few options, just the basic protection, Avira could be your choice.
9. Windows Defender
Windows Defender comes freely with any new Windows system. It’s built into the operating system itself. This is one of its greatest pros when comparing it to other possibilities. Why? Well, just think about it! Any other antivirus program is a third-party application that needs to be installed on to your PC. When you do that, you could slow down your system by a noticeable amount. But what about Defender?
Since, Windows Defender is part of the operating system, it’s a fully integrated program that works together with your system. And as such, it won’t slow down your PC. Like not a bit. If you use Windows Defender, your computer will work at its peak performance, without any lags or drawbacks. Defender being a part of Windows means that there’s no set-up required either. When Windows was installed, so was Defender.
Running it is very simple too. You don’t have to turn it on or do anything else at all. When your PC turns on, so does the antivirus. You get instant protection, with Defender looking out for threats all the time. If you want to check out some of its features, you can easily do that from its dashboard (a very user friendly one).
You can set the program to run custom or quick scans, or even make a scheduled scan when your PC turns on. This is efficient in starting with a clean system all the time. A firewall is built into the program as well, running in real time.
Family Options is also an available feature. Using this, you can control what your kids can use and see online, and also the devices they’re using. But it can do much more than that. You can use it to monitor your business systems and multiple devices too.
Windows Defender has a better detection rate than many of its competitors (Avira, ESET etc) at 98,9 – 100%. Your systems security is assured with this software.
10. Panda Free Antivirus
Panda Free Antivirus is a software that came from the Spanish company called Panda Security. The Windows version doesn’t come with too many features, but it’s still a very good option if you need an antivirus that’s simple and powerful.
Once you download and install the software, Panda will ask you to activate your program. This basically means that you should sign in using your email address and password, or just create a new account if you don’t already have one.
When the activation was completed, the first thing you should do, is a complete system scan. But if you’d like to, you can do a quick or custom scan also. The custom scanning option is pretty limited: you can only choose the specific folder for scanning.
If we’re talking about security, Panda isn’t bad at all. It can detect and stop most of the threats. Some benchmarks even managed to come out with 100% protection rate.
11. AVG Antivirus Free
AVG is now owned by Avast. Does that mean that the software is all the same? No, not really. The engine behind the 2 software is very similar, but besides that, they are 2 different programs. Though you can surely find some similarities.
The set-up is easy to be done and you can use the software in minutes from downloading it. There is no need to sign-up for an account (yes, this is similar), you can use the program as it is. Once all is installed you are prompted with the AVG user interface. From the start, you can see that AVG Free Edition can do 3 main things:
- Computer Security
- Web Security
- Email Security
This means that you get the standard features an antivirus has to offer. Scanning the PC can be done in at least 3 different ways: Full system scan, Quick scan or Custom scan. The third option will give you all the freedom you could need to scan exactly the files/folders you want. You can even check the running processes for malware.
AVG is not bad at all if we think about the protection it gives its user. It will detect and stop most of the threats, while not overwhelming your systems resources.
If you’re looking for a program that will give you flexibility in its features, but should be simple to set up and manage, then AVG could be your thing.
Wrapping Up
During this article we looked at 11 programs that are capable to give your PC the security you desire. And above all, every one of these antivirus programs is free to use. No matter if you just need a simple software or one with lots of features and customizability, you will surely find one among the ones I mentioned in this article.