Instructions & Technical Principle

How to use:

1. Click the file selector and choose a local file from your computer.
2. The tool will automatically compute MD5, SHA-1, SHA-256 and SHA-512 checksum.
3. Click the Copy button to copy each hash value for verification.

Core Principle:
The program reads your file in chunks to avoid excessive memory consumption for large files. MD5 calculation uses SparkMD5 library; SHA family algorithms use browser native Web Crypto API. All computations run locally on your device.

Privacy Guarantee:
Your file content never leaves your computer. No data is transmitted to the web server. You can safely verify confidential documents, archives and media files.

Important Reminders:

• MD5 and SHA-1 are cryptographically insecure. Use SHA-256 or SHA-512 for security validation.
• Large files may take several seconds to finish calculation depending on hardware performance.
• Modifying even one byte of the file will completely change all hash results.