How the target GPA planner works
Your GPA is a credit-weighted average, so every credit you have already earned "locks in" part of your final result. The planner works backwards from your goal: it figures out the total grade points your target requires, subtracts the points you've already banked, and divides what's left by your upcoming credits.
Required average = (Target × (Completed + Upcoming) − Current × Completed) ÷ Upcoming
This is the same math academic advisors use when they tell you whether a goal is realistic. Because the formula accounts for credit weights, it also shows why goals get harder the more credits you've finished: with 90 credits banked at a 2.8, even straight A's in your last 30 credits can only lift you so far.
Worked example
Say you have a 3.0 GPA after 60 credits, you want to graduate with a 3.5, and you have 15 credits left. Required = (3.5 × 75 − 3.0 × 60) ÷ 15 = (262.5 − 180) ÷ 15 = 5.5. Since 5.5 is above the 4.0 maximum, the planner flags this as impossible — no combination of grades in 15 credits can close the gap. Your realistic options: lower the target, or add more credits (a minor, summer courses) so the math has room to work.
Reading your result
A required average near the top of the scale (3.7+ on a 4.0 scale) means you need mostly A's — tough but doable if the remaining courses play to your strengths. A required average below your current GPA means you're already ahead: even average grades keep you on track. And if the planner says "impossible", believe it — the math doesn't bend, but your plan can.