Toolkit / Privacy & Security Tools
File Checksum Calculator
Calculate file checksums such as SHA-256 to verify downloads, compare files, or document file integrity.
Privacy note: Security-sensitive tools are designed for local browser use, but you should only handle secrets on a device and browser profile you trust.
Limitations: A checksum confirms file integrity, not whether a file is safe or malware-free.
File Checksum Calculator
Calculate SHA hashes locally with the Web Crypto API.
Files are read by your browser so the checksum can be calculated on this device.
How file checksum calculator works
Choose a file and hashing algorithm, then Toolkit calculates the checksum in your browser.
Compare the result with a checksum from a trusted source to confirm the file matches.
Privacy
Security-sensitive tools are designed for local browser use, but you should only handle secrets on a device and browser profile you trust.
Limitations
- A checksum confirms file integrity, not whether a file is safe or malware-free.
- SHA-1 is included for compatibility but is not recommended for security-sensitive verification.
- Very large files can take longer to hash and may use significant device resources.
FAQs
What is a file checksum?
A checksum is a short fingerprint calculated from file contents. If the file changes, the checksum changes.
How do I verify a download?
Calculate the checksum and compare it with the value published by the trusted source.
Does a matching checksum mean the file is safe?
It means the file matches the expected bytes. It does not prove the file is harmless.
Which hash should I use?
SHA-256 is a good default for modern integrity checks.