Step 1: Take your total fat grams and add a zero — that's your fat-check number.
Step 2: Cut your total calories in half.
Step 3: If your Step 1 number is lower than your Step 2 number, you pass the test. Example: 25g fat → 250. Calories 800 → 400. 250 < 400 ✓ passes.

Protein is always your friend — aim for it to be the first number you notice. Fat should generally stay low relative to calories (use the 10x Rule above). Watch total carbs on lower-carb days, but remember fiber subtracts from net carbs. When in doubt, the USDA database link below has everything.