I just guess, I know a cup of veggies (non starchy) is about 5 carbs, greens, almost none, slice of bread whole sprouted 10, , cup of beans or pasta, banana or potato 25..............etc, this is a rule of thumb for what I eat and is common in what I eat, your beans might be higher carbs, or your bread might be higher carb etc.
If you memorize what are the common things you eat and how many carbs they are, you can get pretty close and just make adjustments as needed. I'm a vegan, so it's limited what I pick from anyway!!!!
Love chinese food, veggie chop suey with tofu!!! But I only take a few bites of rice, at 50 quick carbs a cup I find it very hard to control my BG!! I am not a low carber, but rice is just a problem for me.
PS I'm not familiar with carbs and cal, but Calorie King is a free lookup for carbs, fats, calories etc.