According to my experience it takes 1kg to lose 1 cm off your waist. This means that it would take around 5lbs or 2.4kg to lose an inch. Most of the time this rule stands true.
FAQ:
Q: What is the fastest way to lose belly fat?
A: The fastest way to lose belly fat is to go on a high protein, low fat, low carb diet. However keep in mind that this is brutality and not easy.
Q: Should I do core specific exercises ?
A: I don't see why you would do that. Obviously you can train your "core" but don't expect to speed up the process that way. It's all about losing weight.
Q: How long it takes to lose an inch off my waist?
A: Around 2 weeks if you go on a strict low calorie diet. You should be losing 2lbs/1kg a week. This requires you to consume 7 000 calories less than you burn in one week.
Q: Should I keep my training the same when cutting?
A: No, cut volume and just train heavy 2 times a week. Do only compound exercises and go home.
Q: What about cardio?
A: You can add a few days of cardio but in the end of the day it's the diet that makes the difference.
Q: What do you think about starvation mode?
A: I think starvation mode is complete bro science.
Q: Do you recommend any cutting plans?
A: You can read my guideline here.
Q: How long would it take to go from 37 inches waist to 32 inches waist?
A: This is 5 inches which equals around 25 pounds. Keep in mind that you may lose even more due to water weight changes.