Why are percentiles quoted to four decimals?

Because with a million candidates one decimal place is nine hundred ranks. At the top of the distribution the extra digits carry real information.

EducationexamsIndia only

JEE Percentile to Rank Estimator

Rank estimated from a percentile. At the top of a million-candidate exam a hundredth of a percentile point is a hundred ranks, which is why percentiles are quoted to four decimal places.

Also called: jee rank predictor, percentile to rank.

Estimated rank

15,000

About rank 15,000 out of 10,00,000. A percentile of 98.5 means 9,85,000 candidates scored below you. With 1000000 candidates, one hundredth of a percentile point is about 100 ranks.

Candidates below you

9,85,000

Candidates above you

15,000

You are in the top

1.5%

Rank one percentile point lower

25,000

On precision

With 1000000 candidates, one hundredth of a percentile point is about 100 ranks.

How this is calculated

Method and background

How this is calculated

A percentile is the share of candidates below you, so rank is what remains, times the total. The sensitivity at the top is the point: with a million candidates, 99.99 is rank 100 and 99.9 is rank 1,000, so a tenth of a point is nine hundred places. That is why scorecards report percentiles to several decimals and why rounding one is meaningless.

rank = the share of candidates above you, times the number who appeared

P: Percentile
N: Candidates

Worked examples

Each of these is asserted on every build. If a change to the engine ever moved one of these answers, the build would fail before the page could print it.

98.5 in a million

Your percentile: 98.5
Candidates who appeared: 10,00,000

Estimated rank15,000

1.5% of a million

Open this example

the top percentile

Your percentile: 99.99
Candidates who appeared: 10,00,000

Estimated rank100

boundary: where precision matters most

Open this example

Method and limits

What it assumes

A single session with a normalised percentile, which multi-session exams compute differently.

What it deliberately does not model

Multi-session exams normalise across sessions, so the mapping is not exactly linear.
Category ranks are computed within a category and are not derivable from an overall percentile.

Formula version 1.0.0 · definition 1.0.0 · India · Report a problem with this calculator

Frequently asked questions

Why are percentiles quoted to four decimals?: Because with a million candidates one decimal place is nine hundred ranks. At the top of the distribution the extra digits carry real information.