If your Ford is newer (2012+), it likely uses an system. This requires a dealer login or a high-end locksmith tool (like Autel or OBDSTAR) that bypasses the need for manual code entry by connecting to a server.
The math required to turn an Outcode into an Incode is proprietary to Ford. You cannot do it with a pen and paper. You need an algorithm—which is where the calculator comes in. ford incode outcode calculator free
They are almost always viruses.
Ford’s security system (often called the PATS—Passive Anti-Theft System) uses a challenge-response handshake. If your Ford is newer (2012+), it likely uses an system