Other Tools
File Checksum Calculator
Calculate MD5, SHA-1, SHA-256, SHA-512 and CRC32 hashes of a file, then compare an expected checksum.
Files stay in your browser. Chunked processing runs in the background; large files may take time.
For text or hexadecimal input: CRC Calculator – CRC-8, CRC-16 and CRC-32
Calculate and verify a file checksum
A checksum is a compact value calculated from the contents of a file. Use this tool to compare a downloaded archive, installer, document or backup with a value provided by its publisher. The file is read as raw bytes: its name and modification time are not part of the calculation.
How to use it
- Choose one file from your device. Empty files are supported too.
- Click Calculate checksums. Progress shows how much of the file has been processed.
- Copy the result for the algorithm used by the publisher.
- Under Verify a checksum, select that same algorithm and paste the expected hexadecimal value. Uppercase letters and surrounding whitespace are accepted.
- Read the match or mismatch message. Paste only the checksum, without a filename, algorithm prefix or a complete command-line output.
Which algorithm should I choose?
| Algorithm | Hexadecimal characters | Typical purpose |
|---|---|---|
| MD5 | 32 | Comparing older published checksums |
| SHA-1 | 40 | Compatibility with older manifests |
| SHA-256 | 64 | Comparing modern download hashes |
| SHA-512 | 128 | Comparing published SHA-512 hashes |
| CRC32 | 8 | Detecting accidental changes; ISO-HDLC variant |
Use the algorithm stated beside the original value. CRC32 here is CRC-32/ISO-HDLC, not CRC32C. For text, hexadecimal input or other CRC profiles, use the CRC calculator.
Privacy and large files
File contents are processed locally in a browser worker and are not uploaded. The reader processes 256 KiB chunks rather than loading the entire file at once. Large files still need time and device resources, especially when calculating five algorithms. Keep the tab open; cancel to stop processing. Selecting another file clears the previous results.
Why does a checksum differ?
Check that the file version and algorithm match. Incomplete downloads, extraction, edits, text encoding changes and line-ending changes all affect the bytes. Renaming a file alone does not. A zero-byte file also has valid checksums.
Does a matching checksum prove a file is safe?
No. Compare against a trusted publisher’s value. A hash comparison is not a malware scan or a digital signature check. MD5 and SHA-1 are unsuitable for protection against deliberate collisions, and CRC32 is not a cryptographic hash. Prefer SHA-256 or SHA-512 when a trusted source publishes one.