File Hash Calculator

A file hash (or checksum) is a unique cryptographic fingerprint of a file's contents. Even a tiny change to the file will produce a completely different hash. This makes hashes essential for verifying file integrity, detecting tampering, and confirming that downloaded files are authentic and uncorrupted.

For security-critical applications like verifying software downloads, use SHA-256, SHA-384, SHA-512, or SHA3. These are considered secure and resistant to collision attacks. MD5 and SHA-1 are deprecated for security purposes but can still be used for simple checksums or legacy compatibility.

First, obtain the expected hash from a trusted source (usually provided by the software publisher). Then, calculate the hash of your downloaded file using the same algorithm. If the hashes match exactly, the file is authentic and unmodified. Use the verification feature in this tool to compare hashes automatically.

No, all file processing happens entirely in your browser. Your files never leave your device, ensuring complete privacy and security. The tool uses JavaScript to calculate hashes locally without any server communication.

Yes! You can select multiple hash algorithms simultaneously. The tool will calculate all selected hashes in one pass through the file, making it efficient for generating multiple checksums or comparing different hash types.

The tool can handle files of any size, but very large files (several GB) may take longer to process and consume more memory. Files are processed in 64KB chunks to optimize memory usage. For best performance, close other browser tabs when processing large files.

MD5 and SHA-1 have known cryptographic vulnerabilities that allow attackers to create different files with the same hash (collision attacks). They should not be used for security-critical applications like verifying software integrity or digital signatures. However, they're still acceptable for simple checksums or legacy compatibility.

SHA-2 (including SHA-256, SHA-384, SHA-512) is the current widely-adopted standard, used by most software and systems. SHA-3 is the newest standard with a different internal design, offering additional security margins. Both are considered secure, but SHA-2 has broader compatibility and is more commonly used.

Processing time depends on file size and your device's performance. Small files (under 1MB) are processed almost instantly. Medium files (10-100MB) take a few seconds. Large files (1GB+) may take several minutes. The progress bar shows real-time processing status.

No, plain hash functions are not suitable for password storage. While you could technically hash a password, specialized password hashing algorithms like bcrypt, Argon2, or scrypt are designed specifically for this purpose. They include salting and are intentionally slow to resist brute-force attacks. Use our bcrypt or Argon2 hash tools for password hashing.

A failed hash verification means the file's calculated hash doesn't match the expected hash. This could indicate: the file was corrupted during download, the file has been tampered with, you're using the wrong hash algorithm, or the expected hash was incorrect. Try re-downloading the file and verifying again.

Yes, each calculated hash has a copy button that copies the hash value to your clipboard. This makes it easy to save hashes for later verification, share them with others, or paste them into documentation.