In the UK, don't subtract fibre from the carbs, they're listed separately.
If using US sources, the fiber is included in the carbs, noteworthy when doing a quick google search. Quickest trick to know if you need to subtract fibre when using the internet is to check the spelling: fibre - ignore, fiber - subtract.
Like many T1's using nutritional information on foods to work out insulin doses, I just look at the carbs and ignore the 'of which sugars', a carb is a carb.
