How much fat should you eat daily?

The total amount of calories from fat should make up around 30% of your diet.
Each gram of fat contains 9kcals. So for example,
If you were consuming 1500kcals a day then 30% percent of those calories should be fat.
1500kcals / 100 X 30 = 450kcals
450kcals / 9 = 50 grams
So a person consuming 1500kcals a day should consume around 50 grams of fat per day. This does not mean to say all these calories should be saturated fats (bad fats). These calories should be consume with unsaturated and polyunsaturated fats (good fats) as well.
For an average person on a 2000 calorie diet, 20g should be the minimum intake of overall fats, with a maximum of 60g. No one should consume over 20g of saturated fats, and trans fats should be avoided completely.