Quick answer
Class percentile = (class size − rank) ÷ class size × 100. A rank of 12 in a class of 240 gives (240 − 12) ÷ 240 = 95%, which also means you are in the top 5% (12 ÷ 240).
Enter your rank and the number of students. The calculator returns your percentile and the top share of the class.
Related tools: Grade Curve Calculator: Apply a flat or proportional curve to a set of scores. Weighted GPA Calculator: GPA with extra points for honors or advanced courses. Grade Calculator: Percentage grade from points earned and points possible.
How to use the Class Rank Percentile Calculator
- Enter your rank (a whole number, 1 or more).
- Enter class size (a whole number, 1 or more).
- Press Calculate to see the result, and use Reset to start again.
| Input | What to enter | Allowed values |
|---|---|---|
| Your rank | A whole number | ≥ 1 |
| Class size | A whole number | ≥ 1 |
Formula and method
Formula
percentile = (size − rank) ÷ size × 100; top share = rank ÷ size × 100
IEEE-754 double precision; shown to the decimals indicated.
Schools define percentile differently; this uses the share of the class ranked below you.
Worked examples
These examples are verified: each one is an automated test case that the live calculator must reproduce exactly.
Example 1
Inputs: Your rank = 12; Class size = 240.
| Result | Value |
|---|---|
| Percentile | 95% |
| Top share of the class | 5% |
Example 2
Inputs: Your rank = 1; Class size = 150.
| Result | Value |
|---|---|
| Percentile | 99.33% |
| Top share of the class | 0.67% |
Example 3
Inputs: Your rank = 75; Class size = 150.
| Result | Value |
|---|---|
| Percentile | 50% |
| Top share of the class | 50% |
The first line is the headline result (percentile). Below it the class Rank Percentile Calculator lists top share of the class, which describe the same case from other angles. IEEE-754 double precision; shown to the decimals indicated.
Percentile versus top percent
A 95th percentile means you scored at or above 95% of the class. 'Top 5%' is the same fact, written from the other side. The two always add to 100, so the page shows both to avoid confusion.
Ties and rounding
Many schools give tied students the same rank, and some round the percentile up. A rank of 1 gives a percentile of (n − 1) ÷ n, not 100, with this formula. If your school uses a different convention, such as counting students at or below you, your reported figure may differ by a point.
How the result changes with your rank
Holding every other input at the first worked example, this table changes only your rank. It shows how sensitive the answer is to that one value; each row was produced by running this calculator.
| Your rank | Percentile | Top share of the class |
|---|---|---|
| 6 | 97.5% | 2.5% |
| 12 | 95% | 5% |
| 24 | 90% | 10% |
| 48 | 80% | 20% |
What happens with invalid input
These messages are produced by the calculator itself, so you know what to fix.
- Your rank: entering "20" shows "Rank cannot exceed the class size." beside that field and no result.
Choosing between the Class Rank Percentile Calculator and similar calculators
Each row shows what a related calculator on this site asks for and what it returns, so you can pick the one that matches your question.
| Calculator | You enter | It returns |
|---|---|---|
| [Grade Curve Calculator](/education/grade-curve/) | scores, score the top student should get and curve | Curved scores |
| [Weighted GPA Calculator](/education/weighted-gpa-calculator/) | grade points per course, credits per course and extra points per course | Weighted GPA |
| [Grade Calculator](/education/grade-calculator/) | points earned and points possible | Grade |
| [Final Grade Calculator](/education/final-grade-calculator/) | current grade, grade you want and final exam weight | Score needed on the final |
| [Weighted Grade Calculator](/education/weighted-grade-calculator/) | scores and weights | Weighted grade |
Assumptions and limitations
- Rank cannot exceed class size
If a required value is empty, not a number, or outside its allowed range, the form marks that field with a message and shows no result instead of a misleading number. The automated checks deliberately try invalid entries for your rank to confirm this.
Frequently asked questions
Is rank 1 the 100th percentile?
With this formula it is (n − 1) ÷ n, for example 99.6% in a class of 240.
What is a good percentile?
It depends on the use. Colleges and scholarships often quote the top 10% or top 25%.
Does class size change the result?
Yes: rank 12 is the top 5% of 240 but the top 12% of 100.
What does the Class Rank Percentile Calculator calculate?
Percentile from class rank and class size. It returns Percentile and Top share of the class.
What formula does the Class Rank Percentile Calculator use?
percentile = (size − rank) ÷ size × 100; top share = rank ÷ size × 100. Schools define percentile differently; this uses the share of the class ranked below you.
What do I need to enter in the class Rank Percentile Calculator?
You enter Your rank and Class size.
How is the result rounded or limited?
IEEE-754 double precision; shown to the decimals indicated. Rank cannot exceed class size.
What is an example of a class Rank Percentile result?
With your rank 12 and class size 240, the percentile is 95%.
Related calculators
- Grade Curve Calculator — Apply a flat or proportional curve to a set of scores.
- Weighted GPA Calculator — GPA with extra points for honors or advanced courses.
- Grade Calculator — Percentage grade from points earned and points possible.
- Final Grade Calculator — The score needed on a final exam to reach a target course grade.
- Weighted Grade Calculator — Course grade from scores and their weights.
- IQ Percentile Calculator — Percentile of an IQ score on a normal scale.
Sources
- OpenStax, Prealgebra 2e (Rice University): fractions, decimals, percents, ratios and rounding
- NIST Special Publication 811, Guide for the Use of the International System of Units (SI)
Content last reviewed 2026-11-04. Formulas and worked examples are checked by automated tests against independently computed values.