File Hash Calculator

How do I calculate a file checksum online?

Drag and drop your file onto the drop zone or click to browse. The tool computes MD5, SHA-1, SHA-256, SHA-384, and SHA-512 hashes automatically. Processing happens in your browser - the file never uploads anywhere.

How do I verify a downloaded file hash?

Get the official hash from the download source. Drop your file in this tool, then paste the official hash in the Compare field. A green checkmark means the file is verified; red X means it may be corrupted or tampered.

What is the maximum file size supported?

This tool supports files up to 500MB. For larger files, use a desktop tool. Large files may take several seconds to hash as the entire file must be read into memory.

Why does file hashing take longer than text?

Files must be read into memory before hashing. A 100MB file requires reading 100MB of data first. The actual hash computation is fast, but file I/O takes time. Progress is shown for files over 2MB.

Can I hash multiple files at once?

Currently, files are hashed one at a time. Drop a new file to replace the previous one. For batch processing, use a desktop tool or command line utilities like sha256sum.

Is my file uploaded when I hash it?

No. All processing happens locally in your browser using the WebCrypto API. Your file never leaves your device. This is why the tool works offline after initial page load.

Which hash algorithm should I use for file verification?

SHA-256 is the standard for file integrity verification. Most software downloads provide SHA-256 checksums. Avoid MD5 for security-critical verification as it can be spoofed.

Why do I get different hashes for the same file?

Ensure you're comparing the same algorithm (MD5 vs SHA-256 are different). Also check for invisible differences like line endings (Windows vs Unix) or trailing whitespace in text files.