I can say that january (non 1st week) is a non crowd period. But, there are some better qualified info at internt, like: (Trip Advisor do not permite URLs here).
So ask Google for: "disney crowd calendar 2018".
Have a nice trip. You will enjoy it!
January after the first week until mid February avoid MLK and president day. Weekdays always lighter then weekends. Early to mid September. Really the best time with food and wine festival. Again weekdays are better. Truth be told even on a slow day at Disney there are a lot of people.
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