Your file never leaves your device. We compute its fingerprint locally and check it against our threat database.
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Three steps. Zero uploads. Complete privacy.
Select or drag any file into the scanner. It stays on your device the entire time — nothing is ever uploaded to our servers.
We calculate a unique MD5 hash of your file directly in your browser. This cryptographic fingerprint identifies the file without revealing its contents.
The hash is checked against our continuously updated malware signature database. You get an instant verdict: safe or flagged as malware.
Knowledge is your first line of defense against cyber threats.
Malware — short for malicious software — is any program or code designed to harm, exploit, or compromise a computer system, network, or user. Malware can steal sensitive data, encrypt files for ransom, spy on user activity, or turn devices into nodes in a botnet. It is delivered through email attachments, compromised websites, software downloads, and even legitimate-looking applications. Understanding the different forms of malware is essential for protecting your digital life.
Viruses attach to legitimate files and spread when those files are executed. Worms self-replicate across networks without user interaction. Trojans disguise themselves as legitimate software. Ransomware encrypts your files and demands payment. Spyware silently monitors your activity and harvests credentials. Adware bombards you with unwanted advertisements. Rootkits hide deep in the operating system to maintain persistent access. Each type requires different detection and remediation strategies.
The most common infection vector is phishing emails containing malicious attachments or links. Drive-by downloads exploit browser vulnerabilities when visiting compromised websites. Software bundling hides malware inside free applications. USB drives and removable media can carry infected files between air-gapped systems. Supply chain attacks compromise legitimate software updates. Social engineering tricks users into voluntarily installing malicious programs by disguising them as security tools, system updates, or popular applications.
Watch for sudden system slowdowns, unexplained crashes, or high CPU usage when idle. New toolbars, browser redirects, or pop-ups you didn't install are common indicators. Unexpected outbound network traffic, disabled security software, or locked files demanding ransom are serious red flags. Missing files, changed passwords, or unauthorized account activity suggest data theft. If your contacts report strange messages from your accounts, your system may be compromised and sending spam or phishing emails on your behalf.
Keep your operating system and applications updated with the latest security patches. Use a reputable antivirus solution and keep its definitions current. Never open email attachments or click links from unknown senders. Download software only from official sources. Enable multi-factor authentication on all accounts. Back up important files regularly using the 3-2-1 rule: three copies, two different media types, one offsite. Use tools like iMalware to verify suspicious files before opening them, and practice healthy skepticism toward unsolicited messages and too-good-to-be-true offers.
Hash-based malware detection works by computing a cryptographic fingerprint (hash) of a file and comparing it against a database of known malicious file hashes. This method is fast, accurate, and privacy-friendly because only the hash — not the file itself — needs to be transmitted. MD5, SHA-1, and SHA-256 are commonly used algorithms. While hash-based detection cannot identify zero-day threats or polymorphic malware that changes its signature, it remains one of the most reliable methods for identifying known threats and is used by security vendors worldwide as a first-pass detection layer.
No. Your file never leaves your device. iMalware computes the MD5 hash entirely within your browser using JavaScript. Only the hash — a 32-character string — is sent to check against our database. Your file contents remain completely private.
An MD5 hash is a 128-bit cryptographic fingerprint that uniquely identifies a file. Even a single-byte change in a file produces a completely different hash. This allows us to identify known malware by comparing file fingerprints without needing to analyze the file content itself.
Our malware signature database is updated daily with newly discovered threats from multiple intelligence feeds. This ensures you're checking against the most current known-threat data available.
iMalware uses hash-based detection, which is highly effective against known threats. However, it cannot detect zero-day malware (never-before-seen threats) or polymorphic malware that changes its signature. For comprehensive protection, we recommend using iMalware alongside a full antivirus solution with heuristic and behavioral analysis.
There is no hard file size limit. Since the hashing happens in your browser, the speed depends on your device's processing power. Most files under 1 GB are processed in a few seconds on modern hardware. Very large files may take longer but will still work.
Yes, iMalware is completely free to use with no limits on the number of scans. There are no premium tiers, no sign-up requirements, and no ads. We believe everyone deserves access to basic security tools.
Bookmark iMalware and check any suspicious file before opening it. It takes seconds and could save you from a costly breach.
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