18 [ Complete List ] Free Standalone / Portable Antivirus Scanners

Home » Computer and Internet Security » Free Portable USB Antivirus

Is something not quite right with your Windows computer even when you have an antivirus installed? Are you being plagued by pop-up windows trying to get you to download security software or alerts claiming your PC isn’t secure? It appears like your antivirus could have been compromised, therefore a portable antivirus that works alongside your existing antivirus can provide a crucial second opinion on the health of your PC.

See More ▼ Top 16 Free 60, 90 & 180 Days Antivirus Trial – Norton, Kaspersky, AVG, Avast, BitDefender And More

If your Microsoft Windows is infected by malware, chances are, your antivirus has been disabled by the virus or trojan. Uninstalling and reinstalling any antivirus is useless because the malware is programmed to disable it. This is where portable USB antivirus comes to the rescue. Two heads is better than one, having a second opinion from a different security software is better than none. Without further ado, here are the complete list of the best portable antivirus scanner that can be used without installation to scan and clean infected computers.

Windows Malicious Software Removal Tool (MSRT) helps keep Windows computers free from prevalent malware. MSRT finds and removes threats and reverses the changes made by these threats. MSRT is generally released monthly as part of Windows Update or as a standalone tool. MSRT targets prevalent malware families only. For comprehensive malware detection and removal, consider using Microsoft Safety Scanner or any other 3rd party tools listed below.

Pro & Con of Portable Antivirus

Portable standalone antivirus needs to be updated regularly; some antivirus allows you to download the database, while other requires you to download the entire software. Some standalone antivirus are not updated frequently, thus it might not be able to detect the latest malware. Here is the complete list of all portable antivirus, they are compatible with fully featured antivirus.

1. Microsoft Safety Scanner

Microsoft Safety Scanner

Do you think your PC has a virus? The Microsoft Safety Scanner is a free downloadable security tool that provides on-demand scanning and helps remove viruses, spyware, and other malicious software. It works with your existing antivirus software. Microsoft Safety Scanner expires 10 days after downloading. To re-run a scan with the latest anti-malware definitions, please download and run Microsoft Safety Scanner again.

This tool does not replace your antimalware product. For real-time protection with automatic updates, use Windows Defender Antivirus on Windows 10 and Windows 8 or Microsoft Security Essentials on Windows 7. These antimalware products also provide powerful malware removal capabilities.

2. Avira PC Cleaner

Avira PC Cleaner

Avira PC Cleaner is a malware scanner that works alongside other anti-malware products. It protects PCs, laptops and netbooks running Windows XP (SP3) and above. Best of all, PC Cleaner doesn’t require installation, registration or any additional drivers. On-demand scanners are often called second-opinion scanners, as they may be run next to any installed antivirus solution.

The main idea is to verify that resident security software is working correctly and that no malicious software slipped by it. While running on-demand scanners is no guarantee that the system is indeed clean, it increases the likelihood that it is.

3. Comodo Antivirus With Internet Security

Comodo Cleaning Essentials

Comodo Cleaning Essentials (CCE) is a set of computer security tools designed to help users identify and remove malware and unsafe processes from infected computers. Designed as a portable application, the software requires no installation and can be run directly from removable media such as a USB key. CCE consists of two core technologies:

Fully featured malware scanner capable of unearthing and removing viruses, rootkits, hidden files and malicious registry keys hidden deep within a system. The scanner is highly configurable, uses the latest heuristic techniques to detect previously unknown viruses, features first-class malware removal capabilities and is capable of detecting hidden drivers and services loaded during system start-up.

  • Instantly identify and stop every untrusted process running on an endpoint with a single click
  • Powerful antivirus scanner capable of removing malware, rootkits, hidden files and malicious registry keys hidden deep within a system
  • Forensic level stats and graphs allow internal processes and resource usage to be analyzed with unrivaled granularity
  • Integration with Comodo cloud scanners provides real-time safety verdicts for unknown processes
  • Perfect for ensuring network endpoints are totally clean of threats
  • No installation required – can run direct from USB or user desktop via RDP

4. Kaspersky Virus Removal Tool

Kaspersky Virus Removal Tool

They’ve changed the way this software runs now, it is not portable anymore but still perform the scan as usual. Checks for known malware and software vulnerabilities on your PC – plus advises you on your PC’s security status with the free Kaspersky Virus Removal Tool. Kaspersky Virus Removal Tool uses Kaspersky Lab’s latest technologies – plus real-time access to cloud-based security information – to ensure it can scan your PC for the latest viruses and emerging threats.

A very simple quick scan for viruses and malware, during the download of Kaspersky Virus Removal Tool, there will be a download of Kaspersky Security Scan installation files, as well as Kaspersky Software Updater which is an integral part of Kaspersky Virus Removal Tool. Get FREE & quick help for your PC – download an efficient tool to clean up your computer from viruses, Trojans, malware, adware and more.

See More ▼  11 Free Bootable Antivirus Rescue Disc - Fix Unbootable Windows

5. Kaspersky TDSSKiller

Kaspersky TDSSKiller

A rootkit for Windows systems is a program that penetrates into the system and intercepts the system functions ( Windows API ). It can effectively hide its presence by intercepting and modifying low-level API functions. Moreover it can hide the presence of particular processes, folders, files and registry keys. Some rootkits install its own drivers and services in the system (they also remain “invisible”). Remember, TDSSKiller is not a substitute for anti-virus or Internet security software protection. To keep your computer and devices secure, you should install Internet security software.

6. Symantec Norton Power Eraser

Symantec Norton Power Eraser

Eliminates deeply embedded and difficult to remove crimeware that traditional virus scanning doesn’t always detect. Norton Power Eraser is a free tool that can be downloaded and run to remove threats from your computer. You can run this tool to scan for threats even if you have a Symantec product, or any other security product. If you cannot start the computer in Normal mode, you can run this tool in Safe mode. Norton Power Eraser is easy to download, and scans your computer quickly to detect the most aggressive computer viruses. You don’t need to install this tool.

The Norton Power Eraser tool is compatible with computers running Microsoft Windows operating systems only. It does not work with computers running on macOS. Norton Power Eraser uses aggressive methods to detect threats, and there is a risk that it can select some legitimate programs for removal. You should carefully review the scan results page before removing files.

7. Dr.Web CureIt!

Dr.Web CureIt

Run Dr.Web CureIt!® (no need to install it) is Russian antivirus that quickly scan your computer and cure it of any malicious objects. Dr.Web CureIt! is an indispensable tool for curing computers running MS Windows 8/7/Vista/XP/Server 2003/2008/2012 (32- and 64-bit systems). Dr.Web CureIt! detects and neutralizes viruses, rootkits, Trojan horses, spyware, and other malicious objects that have gone undetected by your anti-virus software.

The Dr.Web CureIt! utility will cure an infected system once, but it is not designed to provide your PC with real-time protection from viruses. The utility available on their website always features the latest virus definitions, but its virus databases aren’t updated automatically. Included in Dr.Web CureIt! is a set of virus databases that are only current until a new update is released (usually one or more times per hour).

8. Zemana AntiMalware Portable

Zemana AntiMalware Portable

Clean your computer in minutes, no matter how badly infected! Zemana AntiMalware Free makes it possible! Zamana AntiMalware is an excellent choice to have installed on your computer, because of the low resource consumption you can use the program daily to make sure you’re not infected with any malicious files, and because of the ease to use interface the program is avaiable to every computer user and not only expert.

  • Advanced Malware Detection and Removal
  • Browser Cleanup
  • Effective Against Rootkits and Bootkits

9. Emsisoft Emergency Kit

Emsisoft Emergency Kit

The Emsisoft Emergency Kit contains a collection of programs that can be used without software installation to scan for malware and clean infected computers: Emsisoft Emergency Kit Scanner and Emsisoft Commandline Scanner. The Emsisoft Emergency Kit Scanner includes the powerful Emsisoft Scanner complete with graphical user interface. Scan the infected PC for Viruses, Trojans, Spyware, Adware, Worms, Dialers, Keyloggers and other malicious programs.

10. Sophos’s HitmanPro

Sophos's HitmanPro

HitmanPro is only 12 MB and requires no installation. It can start directly from a desktop, USB Flash Drive, CD/DVD, or a remote storage device. Even if your antivirus is being manipulated by malware or ransomware is getting a hold of your files, HitmanPro functions normally, detecting and removing the threat.

HitmanPro has the ability to remove persistent threats from within your operating system and replaces infected Windows resources with safe, original versions, all while proactively blocking reinfection attempts. A new host of malware is activated every day and can be found everywhere, even on trusted websites, evading regular antivirus programs. HitmanPro is designed to run alongside your antivirus, using its behavioral deep scanning to find and eliminate zero-day, next-gen malware that has avoided detection.

11. ESET Free Online Scanner

ESET Free Online Scanner

Detect and remove malware on your PC with a powerful and user-friendly tool that uses the same ThreatSense® scanning technology and signatures as ESET Smart Security and ESET NOD32 Antivirus — just by using your web browser. One-time scan to remove malware and threats from your computer for FREE.

  • Smart way to test your antivirus – Easy-to-use tool that can run alongside any existing antivirus
  • Comprehensive malware detection – Find and remove viruses, Trojans, spyware, phishing and other internet threats
  • FREE and easy-to-use tool – No commitment, no registration and completely free one-time scan
  • Periodic scanning of your device – Regular and automatic monthly check for infections and suspicious applications

12. TrendMicro HouseCall

TrendMicro HouseCall

HouseCall is Trend Micro’s highly popular on-demand antivirus software scanner for identifying and removing viruses, trojans, worms, unwanted browser plugins, and other malicious software. HouseCall Antivirus includes the following features:

  • Stand-alone eliminates compatibility issues associated with browser-activated scanners
  • Smart Scan delivers the latest antivirus protection while reducing download times
  • Enhanced Detection and Cleanup addresses rootkits and other sophisticated threats
  • Enhanced Scanning performance speeds threat detection
  • Vulnerability scans find threats on other devices connected to your home network
See More ▼  11 Free Bootable Antivirus Rescue Disc - Fix Unbootable Windows

13. F-Secure Online Scanner

F-Secure Online Scanner

F‑Secure Online Scanner helps to get rid of viruses and spyware that may cause problems on your PC, and it works even if you have other security software installed on your computer. F‑Secure Online Scanner is easy to use with just a couple of clicks: just download it and run it. It does not leave anything on your PC. Virus worries? Run a scan for free and get rid of malware.

  • Find and remove viruses, malware and spyware on your PC
  • Easy to use, doesn’t leave anything on your computer
  • Works with any other security software installed
  • Completely free to run and use

14. Panda Cloud Cleaner

Panda Cloud Cleaner

Panda Cloud Cleaner is an advanced disinfector based on Collective Intelligence (scanning in-the-cloud) that detects malware that traditional security solutions cannot detect. Disinfect your computer with Panda Cloud Cleaner, they help you keep viruses at bay. Greater detection capacity than traditional antivirus solutions thanks to its latest generation technologies.

Online detection of all types of malware, vulnerabilities and unknown threats. It is easy to use from your browser and always up-to-date against the latest threats. A free report about threats detected and the status of the security protection installed on your computer.

15. ClamWin Portable

ClamWin Portable

ClamWin is a Free Antivirus for Microsoft Windows. It provides a graphical user interface to the Clam AntiVirus engine. It features high detection rates for viruses and spyware, regular antivirus updates from the ClamAV team, and a standalone antivirus scanner. ClamWin allows for manually scanning individual files, folders, or drives but does not include an always-on background scanner.

16. Sophos Virus Removal Tool

Sophos Virus Removal Tool

Using cutting edge technology found in their enterprise-grade software, this powerful tool detects all types of malicious software on your computer—including viruses, spyware, rootkits and Conficker—and returns it to a working state.

The tool has direct access to virus data from SophosLabs, their global network of threat researchers, ensuring that even the very latest viruses are detected and removed. And it works alongside your existing antivirus. Their free Virus Removal Tool is a quick and easy way to find and get rid of any threats lurking on your computer. Their tool identifies and cleans up infections your antivirus might have missed.

  • Removes viruses, Conficker, rootkits, and fake antivirus
  • Supports Windows XP SP2 and up
  • Works alongside your existing antivirus

17. eScan Anti-Virus Toolkit

eScan Anti-Virus Toolkit

eScanAV Antivirus Toolkit (MWAV) is a FREE utility that enables you to scan and clean Viruses, Spyware, Adware and any other Malware that may have infected your computer. The eScanAV Antivirus Toolkit (MWAV) requires no installation and can be run directly from anywhere, on your computer, USB Drive or from a CD ROM. It can also run if you already have other Anti-Virus software installed on your computer.

The eScanAV Antivirus Toolkit (MWAV) also gets updated on a daily basis with the latest updates to detect spyware and adware released recently, plus the engine is constantly being improved for faster and intelligent detections. Free eScan Antivirus Toolkit Download for Windows® 2012 R2 / 2012 / 2008 R2 / 2008 / 2003 R2 / 2003 / 10 / 8.1 / 8 / 7 / Vista / XP. Scan for Viruses, Spyware and Adware in your computer. Just download and run. No installation of this software required.

18. Avast aswMBR

Avast aswMBR

aswMBR is the rootkit scanner that scans for MBR/VBR/SRV rootkits. It can detect TDL4/3(Alureon), ZAccess, MBRoot (Sinowal), Whistler, SST, Cidox, Pihar and other malware. The current version of aswMBR uses “Virtualization Technology” to improve detection of stealth malware. Please note that to use this feature your machine & CPU must support hardware virtualization.

19. VIPRE Rescue

VIPRE Rescue

[ Discontinued ] VIPRE Rescue is a handy, easy to use tool designed to clean your computer if you are already infected with a virus and your operating system is not working properly as a result of the infection. If you are already running VIPRE and a virus has disabled it, you can still run this program to clean your computer.

20. Symantec Norton Security Scan

Symantec Norton Security Scan

[ Discontinued ] The power and speed of Norton scan technology, available to you for FREE. Scans your computer and lets you know if viruses or malwares are present.
Use Norton Security Scan to determine if your system has been infected with viruses, malware, spyware, or other threats. Newly added — the Cookie Manager that you can use to check for suspicious or dangerous cookies and remove those that raise a concern.

21. BitDefender Quick Scan

BitDefender Quick Scan

[ Discontinued ] Bitdefender QuickScan uses in-the-cloud scanning technology to detect active malware on your system, in under a minute. Because it focuses on active e-threats, the product uses just a fraction of the system resources needed by a regular virus scan and requires no time-consuming virus signature updates, as the detection process is performed by remote Bitdefender servers.

How To Stop Viruses, Trojan and Malware

malware infographic microsoft antivirus Free No Installation Portable USB Antivirus For Removing Scamware And Malware


  1. Gravatar
    Joost de Valk [ Reply ]

    ClamWin Portable Screenshot ClamWin is a Free Antivirus for Microsoft Windows

  2. Gravatar
    jack wallen [ Reply ]

    Five portable antivirus and antimalware tools to carry with you at all

    • Gravatar

      The article writer says they are portable, so I downloaded Kaspersky to test it.
      First of all, it is NOT 700k, it is 124 MEGS.
      Second, I downloaded the initial .exe to my flash drive and clicked install, then when it finally finished I discovered Kaspersky installed itself to my hard drive instead of the flash drive.
      Third, it prompted my to scan my computer without downloading the updated virus signatures.
      Fourth, my guess is that the author wrote this article in 1/2 hour and didn’t bother to actually download and test any of these himself, so it’s a garbage article. Does he get paid by the word and write 20 articles a day?

      • Gravatar
        Ngan Tengyuen [ Reply ]

        Hi erik, sorry for the error, when I use kaspersky Security Scan many years ago, it was portable, probably they changed the way it runs now. I updated the article and added 3 more to the list few days ago. Thanks for informing me, I will update the article.

  3. Gravatar
    Yahoo Answer [ Reply ]

    What is the BEST portable antivirus?

    • Gravatar

      There is more than likely no best. I am about to partition a flash USB drive and install all of these if i can. The next time i suffer an infection, i will just run through as many as i can.

      • Gravatar

        no need to partition – create folders when inserted and install 2-3 on a flash drive.

    • Gravatar

      As for me, it is GridinSoft Trojan Killer Portable

  4. Gravatar
    Fernando Ortega [ Reply ]

    TrustPort Antivirus USB Edition (Portable), Download now!!!

  5. Gravatar
    Aieie Brazov [ Reply ]

    F-Secure On Line Scanner

  6. Gravatar
    frontncenter [ Reply ]

    This is a cookie cutter list of garbage! McAfee? …and Norton? Really??

    It’s no wonder these generic “help/info” sites that push big Corp. crap come up 1st in search engines. lol.

  7. Gravatar
    brian glover [ Reply ]

    The three best portable malware scanners not even listed : 1) Zemana anti malware portable (free) uses several anti virus engines eg Bitdefender and Kaspersky , its very fast & powerful cloud AM
    (2) Emsisoft Emergency Kit doesnt need internet connexion (free) (3) Hitman Pro also uses multiple engines including Bitdefender , free for first use

    • Gravatar
      Ngan Tengyuen [ Reply ]

      Thanks for the info. Zemana and Hitman are freemium, thus not in the list but I think it is worth including. I’ll include all 3 when I update the article.

  8. Gravatar
    brian glover [ Reply ]

    Thanks but Zemana portable free – (Zemana.AntiMalware.Portable.exe) is a recent introduction which is permanently free and not a trial version. It is different to the trial Premium version you show. It is a completely portable cloud version which I use all the time from a usb stick to check for pc infections.

  9. Gravatar

    Comodo requires a reboot – can’t use on servers.

    • Gravatar
      David Klement [ Reply ]

      Comodo Cleaning Essentials doesn’t. Tested on Windows Server 2020 R8 x64

  10. Gravatar

    Microsoft Safety Scanner is NOT Portable….

  11. Gravatar
    anonymous [ Reply ]

    Avira also installed on the hard and superseded and disabled windows defender. I agree with erik that the author didn’t actually test these programs. Incidentally Trend Micro Housecall doesn’t install and it is not even mentioned. I definitely don’t want any of them to install either and both Kaspersky and Avira did indeed install. I gave up after the second. This list is inaccurate if you want to use AVs that don’t install.

  12. Gravatar

    Thank you very much… Had a few Problems in my Registry and no antivirus was working.
    Also i couldnt install a new one… But this gives me hope..
    Thanks for the list

    • Gravatar

      Glary utilities portable to fix the registry errors? It also comes with a worthwhile (though vastly inferior) anti-malware. Though it sounds like you might be in need of a repair disk if your system is that damaged. Kaspersky seems to have one of the best on the market right now but I personally prefer Avira or Avast for rescue disks as Kaspersky has issues on USB.

  13. Gravatar

    Emsisoft has begun to play dirty with non-configurable pop-up ad that always appears whenever the application closes. After more than 10 years in existence, what was a wonderful free backup scanning solution turned into a monstrosity.

  14. Gravatar
    m. edmund howse [ Reply ]

    i only use antivirus apps that work alongside other anti-malware apps, kapersky and so many others want to own our systems so they don’t get my approval

  15. Gravatar
    evebroughtanaxthistime [ Reply ]

    Hello, and firstly thank you for the information; it is what I was l looking for.
    Just have to alert you to Comodo not being free. There is a free version available for phones though. Not to worry, I’ll blast that little asswiggling insect with the other 22 that are hopefully available, and if that doesn’t work, I’ll just pour cough syrup over the machine and call it a day. Thnx again.

  16. Gravatar
    George [ Reply ]

    Symantec Norton Power Eraser seems to be the best as it can also erase some files, but Dr.Web CureIt is not good as it don’t catches anything in my experience.

  17. Gravatar

    Avira dose not support Vista – says so when I try to download it

Leave a Reply

Your email address will not be published. Required fields are marked *