If your job title does not include "chef" of any sort, you are wrong and dishonest to yourself and the person to whom you're presenting yourself to as chef.

If you're a line cook, and actually have completed formal training, it's perfectly fine to say. "Hi, my name is _____, classically trained as a chef, I cook for (this or that place). How are you?"

But don't bullshit yourself, newbie culinary grads in your first or second year in the industry. There's a certain unofficial badge of honor that you must not only understand wholly, but attain by being a line cook. That's the only way you really earn the right to call yourself a Chef, someday. By being a grunt on the front line, and fighting the slammed shifts that would make lesser people cower and walk off the line permanently.

Be proud you're a fucking line cook. Just because you have been trained formally and completed your training as a Chef. Does not make you one.

Being a chef, unless you're weakly just HANDED the position, as some of you/us sadly are, takes time. Steps, and layers. Time and pressure.

I had a guy who would always introduce himself as a chef at one of the places I worked. He manned the fryer and made salads, and ran donkey to stock for us as we needed during service.

Some people are ashamed, or have inflated ego, etc. Some people don't have enough life experience to understand the differences between one and the other, so they have no lines that blur.

But mostly, if I see you, or one of my boys doing that. I'll come by and tell you to quit the shit, and teach you the same thing I mentioned. If you've completed classical training, you may tell people you're trained as a chef, and cook FOR _______.

Source: I've been in the shit for a long time. Cheers.