How many questions can I miss, or need right, for a target score?

Enter the total number of equal-value questions and your target percentage. This rounds to whole questions in your favor: it will never tell you that a fractional question is enough.

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How we calculated this

The exact number of questions a target percentage requires is rarely a whole number, so this rounds the minimum correct up and the maximum missed down, since a test cannot award or forgive a fractional question. Using the example values above, a 90% target on 50 questions requires a raw 45.0 correct; rounded to a whole question, that is 45 correct, meaning you can afford to miss at most 5.

Limitations

This assumes every question is worth the same amount. If your test has unequal-value questions, this calculator will misstate your target; use Test Percentage with your actual points earned and possible instead.

Common mistakes

A frequent error is applying this tool to a test with a mix of multiple-choice and free-response questions worth different point values, since "questions" only functions as a clean unit when every question genuinely counts the same. If in doubt, count total points instead of total questions and use a points-based calculator.

Frequently asked

Why do the two numbers not simply add up the way I expect?: They do add up to the total question count; the rounding is chosen so that hitting the minimum-correct number, or staying within the maximum-missed number, both guarantee your target percentage or better.
What if my target itself is not a whole percentage?: That is fine; the target can be any percentage. Only the question counts in the result are rounded, since partial questions are not something a real test can award.
Why is the minimum correct rounded up rather than down?: Rounding down could land just short of your target percentage; rounding up guarantees the minimum-correct count actually meets or exceeds it.
Can I use this for a quiz with only a few questions?: Yes; the same rounding logic applies regardless of how many total questions there are, though very small counts naturally produce coarser jumps between possible results.

Next decision

If you already know your score rather than a target, use Test Percentage to see where you actually landed.