High Starting gravity

I just finished an IPA and the starting Gravity was 1.100. I added some brown sugar during the boil and it's quite a difference from suggested gravity of 1.063. Will my batch be ok?

Extract brew? It is most likely a case of the wort not being fully mixed. It is very common for extract to not be fully mixed in with the top off water causing false hydrometer readings that are way too high or way too low depending on if your sample is mostly extract if your sample consists mainly of top off water. If you really have a gravity of 1.100, then I would pitch at least 2 packs of dry yeast (maybe 3) or make a MONSTROSITY of a starter for liquid yeast.

As long as you pitch enough yeast and aerate sufficiently, the beer will turn out fine. It just will have REALLY high ABV (10-12% depending on attenuation)

Thanks! I ended up pitching more yeast.

The difference between 1.063 and 1.100 is 4 lbs of brown sugar in 5 gallons.

If you added about 4 lbs, then your sample was probably correct. If you added much less, then the wort was probably not mixed properly.

What yeast? With that much simple sugar, you could easily attenuate down to 1.010 or even much lower. If it goes down to 1.010, that will be about 12%, which will be hard work for a lot of yeasts.

How big is batch and how many yeast did you pitched?
For high gravity beers it is recommended to pitch 1M/ml/°P since there will be huge pressure on yeast.