SHA-1 hash for « 3c4f626a65637420786d6c6e733d22687474703a2f2f7777 772e77332e6f72672f323030302f30392f786d6c64736967 23222049643d226f626a656374223e736f6d652074657874 0a2020776974682073706163657320616e642043522d4c46 2e3c2f4f626a6563743e »

What is a SHA-1 hash?

SHA-1 (Secure Hash Algorithm, 1st version) is an algorithm which converts a given sequence of characters into another unique sequence of characters, with a fixed length, called "hash". For instance, the SHA-1 hash of the word password is 5baa61e4c9b93f3f0682250b6cf8331b7ee68fd8.

These hashes are mostly used to validate file integrity, to encrypt sensitive data (like passwords), and to generate unique identifiers.

Is it secure?

SHA-1 hashes are theoretically impossible to reverse directly, ie, it is not possible to retrieve the original string from a given hash using only mathematical operations.

Most web sites and applications store their user passwords into databases with SHA-1 encryption. This method appears to be safe as it seems impossible to retrieve original user passwords if, say, a hacker manages to have a look at the database content.

Unfortunately, there is a way to decrypt a SHA-1 hash, using a dictionary populated with strings and their SHA-1 counterpart. As most users use very simple passwords (like "123456", "password", "abc123", etc), SHA-1 dictionaries make them very easy to retrieve.

This website uses a SHA-1 reverse dictionary containing several millions of entries, which you can use with SHA-1 hashes from your application.

If some of the hashes you enter can be reversed, consider using another way of generating hashes, like using stronger algorithms (SHA-2, Whirlpool, etc), combining algorithms, and using a "salt".