If you want a simple, no-nonsense malware program that does everything for you, Bitdefender Antivirus Free Edition should do the trick with its all-automatic approach to security.
Editor's note: Bitdefender has decided to discontinue Bitdefender Antivirus Free Edition, effective Dec. 31, 2021. Until then, Tom's Guide readers can still download it at this link, but support will end on June 30, 2022.
Malware protection: Very good
System impact, background: Light
System impact, scans: Moderate
Windows compatibility: 7 through 10
Email scans: No
File shredder: No
Game/silent mode: No
Hardened/secure browser: No
Password manager: No
Performance scanner: No
Ransomware file reversal: No
Rescue disk: Free download
Scan scheduler: No
Support options: FAQs, forums
URL screener: Yes, as a separate free tool
Upsell nag factor: Minimal
There are no options, accessories or choices; you can't turn specific defenses on or off, run a quick scan or schedule scans. But Bitdefender Antivirus Free Edition protects against the worst malware, and it's ideal for anyone who wants to install antivirus software on their own machine — or a grandparent's machine — and then forget about it.
The real winner is Kaspersky Security Cloud Free, which offers the best malware protection and has a decent number of extra features, lots of customization options and a very light system-performance impact. It's our choice for the best free antivirus software.
Read on for our full Bitdefender Antivirus Free Edition review.
Bitdefender Antivirus Free Edition: What's covered, and upgrade options
Bitdefender Antivirus Free Edition uses the same malware-stopping technology as the company's paid software. The program has a web filter to block malicious sites and protect against phishing and spam, and monitors the system for potentially malevolent behavior.
The cheapest paid program is Bitdefender Antivirus Plus (starting at $40 per year), which comes with a password manager, a secure browser, a file shredder and an on-screen keyboard. It's one of our choices for best Windows 10 antivirus.
Bitdefender Internet Security (starting at $60 per year) adds webcam protection, a firewall, a vulnerability scanner and parental controls. Bitdefender Total Security (starting at $90 per year) adds licenses for Bitdefender's Mac, Android and iOS protection software, a system optimizer and the ability to track a lost or stolen laptop. Bitdefender Family Pack is a version of Total Security that can cover up to 15 systems for $120 a year.
All the Bitdefender paid programs to this point include client software for Bitdefender's VPN service but are limited to 200MB of data per day. To get unlimited VPN service, you can pay an additional $40 per year or trade up to Bitdefender Premium Security, a version of Total Security that costs $150 per year for 10 devices and also includes priority tech support.
Bitdefender Antivirus Free Edition supports Windows 7 (with Service Pack 1), Windows 8/8.1 and Windows 10.
Bitdefender Antivirus Free Edition: Antivirus protection
Bitdefender Antivirus Free Edition's protection scans for known malware, looks for potentially dangerous behavior such as malicious encrypting of key files, and uploads suspicious files to Bitdefender's servers for analysis. Malware-definition updates are dispersed to 500 million users worldwide several times daily.
There's little in the way of adjustment and customization. Forget about toggling major features on or off or choosing what the program scans for. Everything is automatic, except the scanning of USB flash drives when they're plugged in — you have to manually right-click the drive in Windows Explorer or drag-and-drop its contents onto the main Bitdefender interface.
Bitdefender Antivirus Free Edition: Antivirus performance
In recent evaluations conducted by independent malware-testing labs, Bitdefender did very well, although it showed a tendency to make false warnings.
Over all 24 of German lab AV-Test's monthly evaluations in 2018 and 2019, and in the first four tests of 2020, Bitdefender detected 100% of known "widespread" malware in every time, but missed some previously unseen "zero-day" malware three times.
Only Kaspersky did better, detecting both types of malware all the time until it finally stumbled in April 2020 with a 99.0% detection rate of zero-day malware.
Windows Defender was in the middle of the pack, consistently detecting either 100% or 99.9% of known malware, but missing the mark with zero-day malware seven times over 28 months.
However, Bitdefender registered the most false positives — 47 — among all five malware engines over those two-plus years. Microsoft had 39 and Avast and AVG 26 each, while Kaspersky had only three, indicating a well-tuned detection engine.
In Austrian lab AV-Comparatives' February-May 2019 series of tests, Bitdefender's defenses were nearly perfect, stopping an average of 99.9% of online malware and racking up just two false positives. Kaspersky was indeed perfect, with a 100% detection average and zero false positives.
The positions were reversed in the July-October 2019 round, in which Bitdefender got 99.7% and Kaspersky 99.1%, although the false-positive scores remained the same. In Febuary-March 2020, the results swung back Kaspersky's way; it got a perfect 100% while Bitdefender got only 99.5%, but neither had any false positives.
Among the other three brands, Microsoft's malware engine may have been a bit too aggressive, as its Windows Defender had a decent 99.6% detection rate but a whopping 74 false positives in the earlier round, and 99.3% in the second round with 58 false positives.
Microsoft told us that the high false-positive counts were a result of its Smart Screen feature flagging anything unknown as potential malware, and AV-Comparatives chalking up a false positive every time that happened.
For its February-March 2020 tests, AV-Comparatives reportedly turned Smart Screen off, and Defender came away with only five false positives and an overall detection store of 99.7%.
Avast and AVG had the opposite problem: only five false positives each but underwhelming 99.2% average detection rates in the February-May round, and 99.3% with eight false positives each in July-October. In February-March 2020, they each scored 99.7% with five false positives, the same as Windows Defender.
We normally use test results from Britain's SE Labs, but Bitdefender stopped being tested in mid-2018 after it got mediocre scores for neutralizing some malware rather than completely removing it.
Bitdefender Antivirus Free Edition: Security and privacy features
Bitdefender Antivirus Free Edition's minimalist features range from anti-phishing defenses to warnings of known malicious websites. That's all that comes with the software.
Bitdefender Antivirus Free Edition: Performance and system impact
Bitdefender Antivirus Free had a moderate impact on system performance as measured by our custom benchmark test, which clocks how long a CPU takes to match 20,000 names and addresses in an Excel spreadsheet.
We used an Asus X555LA notebook with a 2-GHz Core i3-5005U processor, 6GB of RAM and 59.5GB of files on a 500GB hard drive. It used Windows 10 with the latest updates.
Before we installed Bitdefender Antivirus Free Edition, we ran the benchmark to provide a baseline for comparison. The CPU took an average of 13.7 seconds to complete the test. The time rose to 14.0 seconds after Bitdefender Antivirus Free was loaded, but before it started scanning.
The 2.1% background slowdown was the second best of the free antivirus programs, just behind Kaspersky Security Cloud Free, which actually sped up the system by 0.9% after its installation.
Bitdefender Antivirus Free was slow to complete its first full scan, which took 1 hour, 4 minutes and 47 seconds. That improved dramatically after the first go-round, because the program had learned what to ignore and what to examine.
On subsequent scans it averaged 3 minutes and 38 seconds, which was so quick that it doesn't matter if Bitdefender Free lacks a quick-scan option.
However, active scanning slowed system performance considerably. Our data-matching benchmark took an average of 17.7 seconds to complete its tasks while Bitdefender Antivirus Free ran full scans.
That's 29% slower than the preinstallation baseline, matching Avast's, and 26% slower than the background load after installation.
By comparison, AVG's full scan slowed the system by 13% from the baseline and 7.1% from the background. Windows Defender's full scan caused a 20% slowdown from the background. Kaspersky was the speed champ, slowing things down by only 1.1% from the baseline.
Bitdefender Antivirus Free Edition: Interface
Bitdefender Antivirus Free Edition's interface is open and accessible but overwhelmingly dark. The black main window has a large green checkmark when everything is good, or a red X when things aren't so good. Below that are listed the last four tasks the software has performed, including scans and updates.
The gear icon in the upper right opens the few options available. The Events section mirrors the main page's recent activity, Quarantine is for caught malware and Exclusions is for whitelisting safe items. The Protection section shows which versions of the software and engine are in use and lets you turn the Protection Shield on and off.
Account Info lets you log into your Bitdefender Central account, stop Bitdefender upgrade reminders and end malware information-sharing. But there's no way to force a malware-definition update.
The program's System Tray icon is a disappointment, as all it does is open the main interface window. Other free AV programs' System Tray icons give status checks, look for definition updates and start scans.
Bitdefender Antivirus Free Edition: Installation and support
The first step is to download and run the 10.1MB installer program, which in turn downloads the 384MB main installer. In our case, the process ground to a halt after 14 minutes. It took an extra 6 minutes and two reboots to get it done. Your experience should be better.
The next step is to set up a Bitdefender Central online account to monitor your security and those of other devices with Bitdefender software installed. You will need to respond to an email verification check.
Bitdefender Antivirus Free Edition's Help and Support section is a thinly veiled attempt to get you to upgrade to a paid subscription (and, thankfully, about the only one you'll encounter), but there's a link to send the company feedback.
There's no guaranteed telephone or chat tech support with Bitdefender Antivirus Free Edition. Instead, there are lots of online help available for common problems along with videos and reports of recent hacks. However, we were able to start a live chat with a tech-support agent with no problem from the Bitdefender support website.
Bitdefender Antivirus Free Edition review: Bottom line
Bitdefender Antivirus Free Edition makes a virtue out of being basic and automatic. It lacks customizability, options and extra features. Its protection is good, and the program can whip through a hard drive in record time. But its initial scan seems to take forever, there's no quick-scan option and you can't even schedule scans.
If you want more extras, Avast Free Antivirus comes with a lot of goodies, but its malware protection isn't that good. Your best bet will be Kaspersky Security Cloud Free, which aced nearly all the protection tests, has a good number of extras, is highly customizable and had a very light system impact on our test machine.
Updated with latest lab-test results. This review was originally published in May 2020.