I don’t have a specific date suggestion, but some general guidelines that get shared a lot:
1. Don’t go by what any crowd calendar says. They are totally inaccurate. Don’t factor them in. Don’t even look at them. Don’t let them sway your decision.
2. If your main goal is avoiding crowds, then avoid any holiday weekend where people will have Friday or Monday off for a 3 day weekend because those will have higher attendance.
3. Generally speaking, aim for Tuesday, Wednesday, Thursday on a week that doesn’t have a holiday on either end for lowest crowds. However, note that entertainment availability may be less on these days.
4. If you have to go over a weekend, Saturday and Sunday aren’t necessarily bad, as long as you are prepared for a decent sized (but not necessarily insane) crowd. (I visit most weeks almost exclusively on the weekends).
5. I can’t explain this but Monday’s often seem very crowded regardless of whether it’s a holiday or not. They can feel even more crowded than weekends.
6. Any special promotions, festivals, holidays, or celebrations that Disney is running will bring people to the park, especially if it’s the first day of the special event, or the first weekend of it.
7. major conventions in Anaheim can increase park attendance. That may not be as big of a factor this year though.
8. Regardless of the day you go...
Getting to the park for rope drop (or early entry) will be the best way to avoid crowds. You’ll feel like you are ahead of the crowd all day long.
Understand how to use FastPass, and even better MaxPass. And Mobile Order!
And the most important tip of all: attitude is everything. If you go in expecting low crowds, then even medium size crowds will feel unbearable. If you go in expecting a huge crowd, armed with good strategies to deal with them, then even the most crowded day can be stress free and fun.