While most computers come with built-in antivirus software, no single program can catch every threat. Using an online virus scanner provides an extra layer of protection and a second opinion on your system’s security. This guide covers some of the best free online tools to scan your computer for malware and viruses.
Browser-Based File Scanners
Browser-based scanners allow you to upload individual files or URLs for analysis without installing any software.
VirusTotal
VirusTotal is one of the most comprehensive online scanning services available. It analyzes suspicious files and URLs using over 70 antivirus scanners and URL/domain blocklisting services.
To use VirusTotal:
Step 1: Go to virustotal.com
Step 2: Click “Choose file” to upload a file or paste a URL into the search bar
Step 3: Wait for the scan to complete and review the detailed results
VirusTotal provides a breakdown of detections from each antivirus engine, file details, and behavioral information. This makes it an excellent research tool for investigating potential threats.
Jotti’s Malware Scan
Jotti’s Malware Scan is another popular multi-engine online scanner that checks files against 20+ antivirus programs.
To use Jotti’s:
Step 1: Visit virusscan.jotti.org
Step 2: Click “Choose File” to select a file from your computer
Step 3: Review the scan results showing detections from various antivirus engines
Jotti’s provides a straightforward interface for quick file analysis without requiring registration.
Downloadable On-Demand Scanners
These tools require a small download but offer more thorough system scans.
ESET Online Scanner
ESET Online Scanner is a lightweight, on-demand scanner that can detect and remove threats without conflicting with existing security software.
To use ESET Online Scanner:
Step 1: Go to eset.com/online-scanner
Step 2: Click “Download Now” and run the installer
Step 3: Choose your scan options (Quick, Full, or Custom)
Step 4: Review the results and select threats for removal
ESET Online Scanner updates its virus definitions before each scan to ensure it can detect the latest threats.
Microsoft Safety Scanner
Microsoft Safety Scanner is a free downloadable security tool that provides on-demand scanning and malware removal.
To use Microsoft Safety Scanner:
Step 1: Download the tool from microsoft.com/security-scanner
Step 2: Run the executable and choose a scan type (Quick, Full, or Customized)
Step 3: Allow the scan to complete and review the results
Step 4: Restart your computer if prompted to complete malware removal
Microsoft Safety Scanner is designed for use with Windows Defender or other antivirus software and expires 10 days after download, requiring a fresh copy for future scans.
Specialized Scanners
These tools focus on specific types of threats or vulnerabilities.
Emsisoft Emergency Kit
Emsisoft Emergency Kit is a collection of tools for detecting and removing malware, particularly useful for cleaning infected systems.
To use Emsisoft Emergency Kit:
Step 1: Download the kit from emsisoft.com/emergency-kit
Step 2: Extract the files and run start.exe
Step 3: Choose “Scanner” from the main menu
Step 4: Select your scan type and follow the prompts to complete the scan and remove threats
Emsisoft Emergency Kit can be run directly from a USB drive, making it valuable for technicians or for cleaning infected systems that won’t boot normally.
Kaspersky TDSSKiller
Kaspersky TDSSKiller is a specialized tool for detecting and removing rootkits, a particularly stealthy type of malware.
To use TDSSKiller:
Step 1: Download TDSSKiller from kaspersky.com
Step 2: Run the executable and click “Start scan”
Step 3: If threats are found, select them and click “Continue” to remove
TDSSKiller is particularly useful if you suspect a rootkit infection, as these can often evade standard antivirus scans.
While online virus scanners provide valuable additional protection, they shouldn’t replace a full-featured, real-time antivirus solution. Use these tools in conjunction with good security practices like keeping your software updated, being cautious about downloads, and regularly backing up your data.