Hash Calculator
Click to upload, or drag a file here
Drop a file or click to pick one — it never leaves your computer
About Hash Calculator
Paste some text and SHA-256, SHA-1, SHA-512 and CRC32 are computed together, updating as you type. Switch to the File tab to hash a whole file — it never leaves your computer.
Why four algorithms on one page
The checksum someone hands you might be SHA-256, or an older SHA-1, or a CRC32 from a legacy system. Getting all of them at once saves the tab-hopping; drop the expected value into the Verify box and a match turns green.
Are SHA-1 and MD5 still usable
For integrity checks, yes: compare the value after a download and you know the file arrived intact. For storing passwords, no — both have practical collision attacks. Use bcrypt or argon2 for anything password-shaped.
CRC32 is not security
It exists to catch transmission errors. Four bytes, trivially collidable. Never treat it as a security check.
Large files
The browser has to read the whole file into memory. For hundreds of megabytes use the command line: sha256sum on Linux and macOS, Get-FileHash on Windows.
Frequently asked questions
Why is SHA-256 so much longer than MD5?
SHA-256 is 256 bits — 64 hex characters — while MD5 is 128 bits, or 32 characters. A fixed output length regardless of input size is the whole point of a hash.
Will the same file give the same value on another computer?
Yes. SHA and CRC32 are deterministic: identical bytes always produce identical output, which is exactly why they can verify a transfer.
Why does a big file pause for a moment?
The browser reads the entire file into memory before handing it to Web Crypto, so hundreds of megabytes take that much RAM and briefly block the page. For very large files the command line is faster and lighter.
