Because Alpine keeps their database more secure than other brands, "free" instant generators are rare and often unreliable. Your best options include:
Some open-source projects claim to calculate codes for older Alpine models (pre-2005). These usually require: alpine radio code generator
Factory radios (made for Honda) use a different algorithm than aftermarket radios (bought at Best Buy). Ensure your generator service explicitly matches your radio type. Because Alpine keeps their database more secure than