The "Smart Car Tan Code Calculator" is an unofficial software program that mimics this backend server. Instead of paying a dealership for each procedure, a user can input the vehicle's VIN or the request code from the DAS software, and the calculator will generate the necessary TAN code locally, bypassing the official system entirely.

If you own a 2011 Smart Fortwo (or any Smart car from the 450, 451, or early 454 series), you have likely encountered a cryptic, three-number sequence flashing on your dashboard. This is the (Tankentleerungs-Nummer or Tank Entleerungs Nummer), and without it, basic maintenance tasks like changing a fuel pump, cleaning a fuel filter, or replacing the entire fuel tank become an expensive trip to a dealer.

Used for key learning (programming) and activation of extra features.

If you are currently working on a programming project for this vehicle, let me know:

Only download TAN calculators from trusted, vetted sources. Scan all files with multiple antivirus engines before execution. Consider using a dedicated, air-gapped laptop for diagnostic work to minimize risk to your primary computer.

A mechanic without a TAN calculator will likely refuse the job. A dealer will charge you 1 hour of labor (typically $150-$250) just to punch in the code — on top of the actual repair.