File Hash Scanner

Calculate SHA-256, SHA-512, SHA-1, and MD5 checksums for any file. Verify downloads and detect tampering.

Drag & drop a file here, Ctrl+V to paste, or

Any file type No size limit • Never uploaded

4 Algorithms

SHA-256, SHA-512, SHA-1, and MD5 calculated simultaneously.

Hash Verification

Paste an expected hash to instantly verify your file.

100% Private

Web Crypto API. Files never leave your device.

What hashes prove

A cryptographic hash is a unique digital fingerprint. If even one byte of a file changes, the hash changes completely. Two files with the same SHA-256 hash are mathematically identical. This verifies file integrity, detects tampering, and proves authenticity — useful for legal evidence and chain of custody. Learn more in our file hash guide.

How to use it

Calculate the hash of an original file and record it. Later, hash the file again and compare. If they match, the file hasn't been modified. All processing uses SubtleCrypto in your browser — files never leave your device. For photo-specific verification, combine with the Authenticity Checker.

Frequently Asked Questions

What is a file hash?

A hash (or checksum) is a fixed-length string of characters generated from a file's contents using a mathematical algorithm. It acts as a unique fingerprint — even changing a single byte in the file produces a completely different hash. This makes hashes ideal for verifying file integrity.

Which hash algorithm should I use?

SHA-256 is the current standard for security and integrity verification. It's used by most software publishers. SHA-512 provides stronger security for high-sensitivity use cases. SHA-1 and MD5 are included for legacy compatibility but are cryptographically broken — don't rely on them for security purposes.

Is my file uploaded to a server?

No. All hash calculations happen entirely in your browser using the Web Crypto API (for SHA) and pure JavaScript (for MD5). Your files never leave your device. This is safe for sensitive files like encryption keys, certificates, or proprietary software.

How do I verify a downloaded file?

Software publishers often provide a SHA-256 hash alongside their download links. After downloading, upload the file here and paste the published hash into the "Verify Hash" field. If it matches, your download is authentic and wasn't corrupted or tampered with during transfer.

Is there a file size limit?

There's no hard limit — processing happens in your browser using your device's memory. Files up to a few hundred MB work well on most devices. Very large files (1GB+) may take longer but will still process. The time shown in results tells you how long the calculation took.

Why is MD5 considered insecure?

MD5 is vulnerable to collision attacks — it's possible to create two different files with the same MD5 hash. This means MD5 can't reliably prove a file hasn't been tampered with. It's still fine for quick non-security checks (like detecting accidental corruption), but use SHA-256 for any security-related verification.

Can I compare two files?

Yes — scan each file separately and compare their SHA-256 hashes. If the hashes are identical, the files are byte-for-byte identical. If they differ by even one character, the files are different. You can also use the "Download All Hashes" button to save results for later comparison.

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