File Hash Checker
MAG212 CYBER · Tools
File hash checker.
Verify that a download — a Cisco IOS XE image, an ISO, an installer — is exactly what the vendor published. Calculate SHA-256, SHA-512 and more, and compare with the published value. The file never leaves your computer.
Check a file
🔒 Hashing uses your browser’s built-in Web Crypto API. The file is read locally and never uploaded. MD5 is not offered: it is broken for security purposes — use the SHA-512 or SHA-256 value most vendors (including Cisco) now publish.
Command-line equivalents
| Platform | Command |
|---|---|
| Windows PowerShell | Get-FileHash .\file.iso -Algorithm SHA256 |
| Windows Command Prompt | certutil -hashfile file.iso SHA256 |
| macOS | shasum -a 256 file.iso |
| Linux | sha256sum file.iso · sha512sum file.iso |
| Cisco IOS / IOS XE (on the device) | verify /md5 flash:<image>.bin — newer releases also offer SHA-512; check with verify ?. For signed images, also run show software authenticity file flash:<image>.bin. |
Why verify hashes?
- A hash is a fingerprint: change a single bit of the file and the hash changes completely.
- Matching the vendor’s published hash proves the file wasn’t corrupted in transfer or swapped by an attacker on a mirror, proxy or file share.
- Get the expected hash from the vendor’s own website over HTTPS — not from the same place you downloaded the file.
- Hashes show integrity, not trust. For software you install, also check the digital signature where the vendor provides one.
Need expert help?
MAG212 CYBER offers network and cybersecurity consultation, plus security seminars for organisations around the world.
