Just bought a packet of pumpkin seeds from Lidl. (they are green in colour, but the packet does not state if they are roasted, dried etc.)
The nutritional information on the packet states that 100g contains 569kcal, and 1.9g carbs.
However, if you look at Calorie King for example, it says 100g contains 540kcal and 17.8g carbs.
My Fitness Pal is different again. and just googling “calories in pumpkin seeds” brings up yet more conflicting values.
Which am I to go by??

Well, the Tescos ones are 618kcal and 10.7g carbohydrate per 100g! So I would guess that all are around 550 – 600 kcal but as to the carbohydrate, it’s any ones guess!
On the positive side, I don’t suppose you are going to eat 100g? So, say, 10g would be about 60kcal and only 1 or 2 g carbohydrate at worse!

Funnily enough Bissell, I have been to Tesco this afternoon. I compared 2 packets of what appeared to be identical pumpkin seeds, and both Tesco brand, just slightly different packets. One stated 593kcals/4.7g carbs, and the other just as you said.
Bizarre!