How it's worked out
Your current grade covers everything except the final. If the final is worth w% of the course, then:
For example, with 82% now, a goal of 85% and a final worth 40%: (85 − 82 × 0.6) ÷ 0.4 = 89.5%.
If the answer is 0 or less, you've already locked in your goal. If it's over 100%, the goal is out of reach, and the table shows the best you can finish with.
Questions
How do I calculate what I need on my final?
Take the grade you want, subtract your current grade times the share of the course that's already done, then divide by the final's weight. With 82% now, an 85% goal and a 40% final: (85 − 82 × 0.6) ÷ 0.4 = 89.5%.
What if I need more than 100%?
Then that goal can't be reached with the final alone. The calculator shows the best grade you can still finish with, so you can set a realistic target.
Can I use a letter grade as my goal?
Yes. Type a letter like A- and it uses that letter's cutoff on the scale you choose (Standard US, Ontario or Western).
Does my current grade need to be exact?
Use the grade your school shows for the course so far. If parts are still unmarked, the answer will shift once they are.