What is htpasswd?
htpasswd is a command-line tool of the open-source HTTP server Apache httpd, used to generate password files for HTTP basic authentication.
What is the difference between encryption methods?
MD5:Encrypt passwords with MD5. This is the default encryption on Windows, Netware and TPF.
crypt:Uses crypt() to encrypt passwords. On all platforms except Windows, Netware and TPF this is the default. Although it can be supported by htpasswd on all platforms,\n it cannot be supported by the httpd server on Windows, Netware and TPF.
SHA:Encrypts passwords with SHA. It is designed to make it easier to import or migrate to Netscape, which uses the LDAP Directory Interchange Format (ldif).
plain:No encryption; uses plaintext passwords. Although htpasswd can create such passwords on all platforms, the httpd daemon only supports plaintext passwords on Windows, Netware and TPF.
Why make it online?
If we do not use an apache server, for example when using nginx or similar, we may not have this command line tool at hand and cannot generate a password file; the online version makes it convenient for server administrators.
This tool belongs to the “Encryption & encoding” category.
Your input is processed locally in the browser whenever possible. We do not store it.
No. MD5 is a one-way digest — you can compare it, never reverse it. So-called "decryption" is a rainbow-table hit.
Salts, random IVs, or a different case or source encoding all change the output. Normalise to UTF-8 before comparing.
Use it for learning and format checks. Generate and store production keys server-side; never paste a live secret into a web page.