Inverse Normal Distribution Calculator

Enter your values below to get the result first, then scroll for the full explanation and guidance.

Step 1 • Add values

Use the calculator

Enter your values below to generate an instant result. You can update the inputs at any time to compare different scenarios.

Example verified by the calculator's probability distributions reference cases.

Results refresh instantly as values change.

Normal quantile

1.95996399Lower-tail probability 0.975

Normal quantile: 1.95996399 (Lower-tail probability 0.975)

The inverse standard-normal approximation is scaled by the entered standard deviation and shifted by the mean.

Inverse normal result

The inverse standard-normal approximation is scaled by the entered standard deviation and shifted by the mean.

Result snapshot

A quick visual read of the values behind this result.

z-score1.95996399

Recommended next checks

  • →Enter probability as a decimal strictly between zero and one.
z-score
1.95996399

Try different values to compare results.

Find the normal-distribution quantile for a lower-tail probability, mean, and standard deviation.

Fast to use

Built for comparison

Clear result output

Table of Contents

6

About Inverse Normal Distribution Calculator

Inverse Normal Distribution Calculator helps you work through the main numbers for this topic quickly with a simple input flow and an instant result.

Use the calculator result as a practical starting point, then review the explanation and assumptions on the page if you want more context.

Calculation method

Apply a standard-normal inverse-CDF approximation, then scale by sigma and add the mean.

Formula explained

Calculation flow

This calculator is structured for fast UK-focused estimates with clear inputs, repeatable logic, and instant results.

Formula

Input values -> calculation engine -> instant result

How the result is built

1Enter the values requested in the form.
2The calculator applies the configured formula logic.
3The result updates instantly with a breakdown.
4Use the output to compare scenarios quickly.

Example

Example verified by the calculator's probability distributions reference cases.

Assumptions

  • Finite mean, positive standard deviation, and lower-tail probability strictly between zero and one.

Source basis

  • UK-focused calculator flow
  • Structured input validation
  • Instant result breakdowns

FAQ

Common questions

Finite mean, positive standard deviation, and lower-tail probability strictly between zero and one.

Trust and notes

Assumptions and important notes

This calculator is designed to give a fast estimate using the method shown on the page. Results are most useful when your inputs are accurate and the tool matches your situation.

Use the result as guidance rather than a final diagnosis or professional decision. If the result could affect health, legal, financial, or compliance decisions, verify it with a qualified source where appropriate.

  • Finite mean, positive standard deviation, and lower-tail probability strictly between zero and one.

Method

UK calculator guidance

Last reviewed

April 17, 2026