PFX (original format)

File Format
Name	PFX (original format)
Ontology	Electronic File Formats Security PFX (original format)
Extension(s)	.pfx, .p12
Released	≤1996

Most .pfx files are in PKCS12 format, not the obsolete PFX format described in this article.

PFX (Personal Information Exchange) is a cryptographic container format developed by Microsoft. It has been criticized for being complex and poorly-designed. It was replaced by a (somewhat improved?) successor format, PKCS12.

PFX is used for crypto keys, certificates, and other objects. Multiple objects may be stored in a single file.

Links

• Wikipedia: PKCS #12 - also discusses PFX
• OpenSSL PKCS#12 Program FAQ
• PFX - How Not to Design a Crypto Protocol/Standard [Ed. note: It's not clear how much of this article is about PFX, and how much is about PKCS12.]