How many cals in a jacket potato

Potato around 200 kcal
20 gr Flora look it up online i think it should be around 50kcal
Tuna mayo around 2 tbs around 150 kcal

I do not think it would be more than 400kcal honestly

Search the food database on here and the figures are there.

Large Baked Potato - 278 calories
Flora original 20g - 80 calories
130g tuna in oil (that is 1 tin drained) - 234 calories
1tbsp mayo - 90 calories

Obviously I don't know how much tuna mayo you had, but if it filled a large potato it was probably the equivalent of one can. I also don't know how much mayo was in it, but I put 1tbsp in with a can of tuna so I have based it on that.

So you are looking at around 682 calories.

There are two listings for baked potato with tuna mayo on the database, but they don't have margarine in. They are 595 calories for "Homemade" and 688 for "Weatherspoons".

Unless your potato was very small and you barely had any filling I think 400 is probably too conservative an estimate.

Tuna is usually either in oil or brine (or spring water, but not usually in catering tins).

Tuna in brine is about 150 calories per can. You would tend to put more mayo with it though as it isn't oily already.

So potato + half a tin of tuna in brine + 1tbsp mayo + 20g flora = 278 + 75 + 90 + 80 = 523 calories.

Which is still a good deal more than 400.

Personally if I eat out and don't know how many calories are in something I err on the side of caution and log more rather than less. So I would probably log it as the Wetherspoons one. But that's just me.