Test grade calculator
The difference between an A and a B is often just 2-3 questions on a 50-question test. Getting 45/50 (90%) is an A; 42/50 (84%) might be a B. That's a full letter grade swing on just 3 questions. Grade cutoffs are arbitrary — 89.5% might round to an A at one school and stay a B+ at another. Know your teacher's specific scale.
Good to know
Not all points are created equal. On a 100-point test, each question might be worth 1, 2, 5, or variable points. Partial credit changes everything. "18 out of 25 questions correct" is 72%, but if you got full credit on hard questions and missed easy ones, your point total might be higher than 72%.
Grade boundaries are arbitrary. Why is 90% an A and 89% a B+? Convention, not logic. Some teachers round 89.5% up; others don't. Some use 93% for an A. Always know your specific grading scale before calculating what score you need on a final.
Curves help and hurt. If the class average is 65% and the curve sets C at 65%, your 75% becomes a B+. But curves also mean your grade depends on classmates' performance, not just your own knowledge. A rising tide lifts all boats — and so does a falling one.
Disclaimers & sources
For reference only. Grading policies vary by teacher and school.