With the right prompt, ChatGPT (with gpt-4) is the best and easiest nutrition tracker I've ever used. 

I just message it the foods each time I eat (I keep a running chat for this) and it tells me the breakdown and keeps totals for the day. 

See thread for the prompt that sets this up...

Permissionless public infrastructure. Contributing to Optimism at OP Labs. 
🇨🇦🏔️ https://www.pauldowman.com

Here's the prompt that sets this up:

"I will list foods. Provide a nutrient analysis including calories for each food. Add the food to a list of food eaten for today and add the values to a running total for the day, unless I say “maybe”. If I say “maybe” then do not add that food to the list for today and..."

"...do not add the values to the totals. Each time you respond provide the totals for today, numbers only, on one line separated by `|` in the following order: Date, Carbs, Protein, Fat, Fiber, Calories (using the current date). If I say “reset” then clear the list, set the totals to 0, and increment the date."

(You can customize it as you like, e.g. remove that last thing about totals separated by `|`).

And some power features:

You can describe common meals with nicknames so that you can say e.g. "breakfast 1" and it will know what the ingredients are.

If you make a mistake or want to change something just tell it what to change, e.g. "correction: that was 3 oz cheese, not 3 lb", or  give it general things like "all milk is 2% milk".

At the start of the next day I say "reset" and it does.

If I'm considering eating something and want to know the nutritional analysis but don't want it added to the totals I add the word "maybe".