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Free global education tool · Reviewed 2026-10-01

Hypergeometric Calculator

Calculate exact or cumulative probabilities for drawing a chosen number of successes from a finite population without replacement.

Reviewed by Mohammad QasimMethod and limitations disclosed
Interactive calculatorYour values stay on this device
✓ Estimated result

P(X = 1)

29.947364%

Exact probability for sampling without replacement
P(X ≤ 1)95.831563%
Expected successes0.3846
Personalised from your inputs

How this calculator helps

Calculate exact or cumulative probabilities for drawing a chosen number of successes from a finite population without replacement. This page keeps its calculation method visible and groups only close keyword variants that use the same inputs and result. Use it for a quick, transparent estimate, then verify consequential decisions against the relevant current source or measurement.

How to use it

  1. 1

    Enter your measured values in the units shown beside each field.

  2. 2

    Review the formula and confirm that the inputs match the task you are solving.

  3. 3

    Calculate the result, then adjust one input at a time to compare scenarios.

  4. 4

    Use the limitations and verification guidance before ordering materials or interpreting a score.

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Formula and methodology

P(X = x) = C(K,x) × C(N−K,n−x) ÷ C(N,n), where N is population size, K is the number of successes and n is the draw count.

The calculator applies the disclosed heuristic to values entered on this device. It does not load private admissions data or claim to reproduce an institution's review process.

Worked calculation example

Drawing 5 cards from a 52-card deck can be modeled with N=52, K=4 for aces and n=5.

How to interpret your result

Calculate exact or cumulative probabilities for drawing a chosen number of successes from a finite population without replacement. Read the main result together with the supporting values rather than treating one number as a guarantee. The disclosed method is: P(X = x) = C(K,x) × C(N−K,n−x) ÷ C(N,n), where N is population size, K is the number of successes and n is the draw count.

Input guide

1

Enter your measured values in the units shown beside each field.

2

Review the formula and confirm that the inputs match the task you are solving.

3

Calculate the result, then adjust one input at a time to compare scenarios.

Scenario comparison

ScenarioWhat it demonstrates
Worked baselineDrawing 5 cards from a 52-card deck can be modeled with N=52, K=4 for aces and n=5.
Input quality checkThe result depends on population size, success count, sample size, target count and whether sampling is without replacement. Measure or source the values before entering them.
Units and conventions stress testKeep units consistent. Different pattern, construction, academic or statistical conventions can produce different results.

Common mistakes to avoid

  • Ignoring input quality: The result depends on population size, success count, sample size, target count and whether sampling is without replacement. Measure or source the values before entering them.
  • Overlooking units and conventions: Keep units consistent. Different pattern, construction, academic or statistical conventions can produce different results.
  • Failing to test rounding: Displayed numbers are rounded for readability. Keep unrounded values for intermediate steps and final checks.
How to verify this result

Check the formula, weights and rounding method published by the relevant institution before using the result officially.

Search intent and calculator coverage

Use the hypergeometric distribution when a fixed-size sample is drawn without replacement from a finite population. The page reports exact-count and at-most probabilities plus mean and standard deviation.

Related questions this calculator covers

  • hypergeometric calculator
  • hypergeometric probability calculator
  • sampling without replacement probability

Worked scenarios

ScenarioWhat it shows
Cardscount aces in a five-card hand
Quality samplingestimate defect counts in a finite batch
Classroom problemcompare exactly x with at most x successes

Common mistakes

  • Using a binomial model when draws are without replacement
  • Entering successes greater than population size
  • Mixing P(X = x) with cumulative P(X ≤ x)
How to verify this result

Check that population, success count and draw count match the experiment; compare a small case with direct combinations.

Uses the hypergeometric probability mass function and its finite-population mean and variance.

What can affect the result?

Input quality

The result depends on population size, success count, sample size, target count and whether sampling is without replacement. Measure or source the values before entering them.

Units and conventions

Keep units consistent. Different pattern, construction, academic or statistical conventions can produce different results.

Rounding

Displayed numbers are rounded for readability. Keep unrounded values for intermediate steps and final checks.

Verification

Compare the result with the disclosed formula and a current primary source or qualified professional when accuracy affects a material decision.

Privacy and browser processing

Values entered on this page are processed in the current browser session. SolvePilot does not require an account and does not receive the values entered into the calculator. Refreshing or closing the page clears the working values unless the browser itself restores a previous session. Avoid entering identifying or account information because the calculation needs summary values only.

Accuracy and verification

Accuracy depends first on input quality. Confirm definitions, scales, dates and source information before entering a value. Keep an independent record of any result used for planning because this page does not create an official statement or retain a calculation history.

Limits of this estimate

This hypergeometric is a browser-based estimate, not an official score, engineering design, purchase order or substitute for a tested pattern. It cannot inspect your materials or validate source measurements. Important variables include population size, success count, sample size, target count and whether sampling is without replacement.

Important: Treat the result as a planning estimate. Confirm official requirements and consequential decisions with the relevant institution, authority or qualified professional.

Sources and review information

This tool uses a disclosed calculation and user-entered values; it does not embed private institutional data or guarantee an outcome.Read our editorial and calculation policy →About the author and reviewer →

Frequently asked questions

What does the hypergeometric calculate?+

Calculate exact or cumulative probabilities for drawing a chosen number of successes from a finite population without replacement.

How do I get a more accurate result?+

Use careful measurements and check population size, success count, sample size, target count and whether sampling is without replacement. Keep the units consistent with the fields.

Why can another calculator give a different answer?+

Tools can differ in assumptions, unit conversions, rounding and the exact method they use.

Does SolvePilot save the values I enter?+

No account or personal details are needed. The calculation runs in your browser.

Can I treat this result as official?+

No. It is a transparent estimate or practice calculation. The relevant authority, course provider, pattern maker or qualified professional remains the source of truth.

How can I check the formula?+

Use the formula shown on this page and verify the assumptions that affect population size, success count, sample size, target count and whether sampling is without replacement.