Calculate File Checksums — MD5, SHA-256, SHA-512 Online
A free online checksum calculator that computes MD5, SHA-1, SHA-256, SHA-384, SHA-512, and CRC-32 hashes for any file — directly in your browser. Verify downloaded files, compare two files for differences, detect duplicates, and identify unknown hash types. No file upload, no registration required.
Verify file integrity and generate cryptographic hashes in your browser
| File | Size | Hash |
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Features
How to Calculate a File Checksum
Drag & drop files into the tool or click "Browse Files" to select them from your device.
Select which hash algorithms to compute: MD5, SHA-1, SHA-256, SHA-384, SHA-512, or CRC-32.
Checksums appear instantly in a table. Click the copy button to copy any hash value.
Paste an expected hash into the verification field to check if it matches.
Download results as CSV, JSON, or TXT for documentation or sharing.
Frequently Asked Questions
What is a checksum?
A checksum (or hash) is a fixed-size string computed from a file's contents using a mathematical algorithm. Even a single byte change in the file produces a completely different checksum. This makes checksums perfect for verifying that a file hasn't been modified or corrupted.
Which algorithm should I use?
SHA-256 is the best all-around choice — it's fast, secure, and widely used. Use MD5 only for quick integrity checks (it's cryptographically broken). Use SHA-512 when you need maximum security. CRC-32 is fastest but least secure — good for error detection only.
Are my files uploaded to a server?
No. All hashing is performed locally in your browser using the Web Crypto API. Your files never leave your device. This is verified by the tool working completely offline after the page loads.
How do I verify a downloaded file?
The software publisher usually provides a SHA-256 or MD5 hash on their download page. Drop your downloaded file into this tool, paste the published hash into the verification field, and check if it says "MATCH". If it does, your download is authentic.
Can I hash very large files?
Yes. The tool reads files in 4 MB chunks with a progress bar, so even multi-gigabyte files can be hashed without running out of memory. Processing speed depends on your device — typically 100-500 MB/s.
What is HMAC?
HMAC (Hash-based Message Authentication Code) combines a hash function with a secret key. It's used to verify both the integrity and authenticity of data. Enable the HMAC toggle and enter your secret key to generate HMAC-SHA256, HMAC-SHA512, etc.
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