SellstampHash generator
Generate MD5, SHA-1, SHA-256, SHA-384, SHA-512 and CRC-32 checksums of text or a file, in your browser. Files are never uploaded.
Your file stays on your device
Your browser opens and processes the file itself. It is never uploaded, to Sellstamp or anyone else, and nothing is kept after you close the page.
Building something to sell?
Sellstamp has a storefront, a checkout into your own payment account, automatic delivery and an API with webhooks. Open a free store
How to use it
- Choose text or a file.
- Type the text, or choose the file (up to 500 MB).
- Copy the checksum you need.
Nothing you paste leaves this page
The conversion runs in this browser tab. Nothing is sent to Sellstamp or anyone else, which matters for configuration files, customer exports and tokens.
Which hash for what
SHA-256 and longer are the right choice for anything security-related, and they are computed by your browser’s own Web Crypto implementation. MD5 and SHA-1 are broken for security (collisions can be made deliberately) and are offered only to check a download against a published checksum. CRC-32 detects accidental corruption, not tampering.
For passwords, none of these is suitable on its own: use a password hashing function such as Argon2 or bcrypt on your server.
Questions
How do I verify a downloaded file?
Choose “A file”, pick the download, and compare the checksum with the one the publisher lists, usually SHA-256.
Is MD5 safe?
Not for security: collisions are practical. It is fine for spotting accidental changes.
Can I hash a password here?
You can, but a plain hash is not how passwords should be stored. Use Argon2 or bcrypt.
Is my file uploaded?
No. It is read and hashed in your browser.
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