Practical, plain-English guides to checking files for malware: how to scan a file, which online scanners to trust with which files, and how to judge an unknown file before you open it.
How to Scan a File for Malware
Step-by-step: check one file online, with Microsoft Defender, on a Mac, or from the command line.
Free Online Malware Scanners Compared
Hash lookup vs. upload-based multi-engine scanners: privacy, size limits and what each one can detect.
Is This File Malware?
A practical checklist for investigating an unknown or suspicious file before you open or delete it.
Can PDFs, Images and Documents Contain Malware?
Which file types can carry malware, how, and how to open them safely.
How to Scan a ZIP File for Viruses
Checking archives online and locally, including password-protected and nested ZIP files.
Virus Scan Large Files (No Size Limit)
How to check multi-gigabyte files when online scanners and Google Drive refuse them.
Check a File for Malware Without Downloading It
What you can and cannot check before a file is on your device.
MD5 Hash Malware Lookup
Paste an MD5 hash to check it against the iMalware database of 1,045,564 known malware hashes.