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Calculadora · Maths

Z-Score calculadora

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z
1.5
z = (x − μ) / σ

Convert a raw score into a z-score using z = (x − μ) / σ, plus the two-tailed p-value from the standard normal distribution.

Written by Editorial DeskReviewed by Laura Whitmore

How it works

How Z-Score calculadora solves the problem

This Z-Score calculadora turns a quick question into a straight answer: punch in the numbers, read the z score calculadora, move on with the day.

Think of Z-Score calculadora as the back-of-the-envelope version of the calculation, only the envelope is a web page and the arithmetic is audited by our test suite.

It looks tidier when the working shows — then nobody argues with the answer. Picture the problem as a real-world quantity — then crunch the numbers and the rest of this page explains what the answer means.

Convert a raw score into a z-score using z = (x − μ) / σ, plus the two-tailed p-value from the standard normal distribution.

On this page you will see Standard normal distribution, p-value and Z-score treated as first-class terms — each one is linked to the calculators and references that use it, so you can follow the thread without retyping queries into a search bar.

If it helps, jump straight to the Maths hub or compare with the Standard Deviation Calculator and the Mean (Average) Calculator — those two calcs are the ones readers usually open right after this page.

One scenario, fully unpacked

Put the method down against a real situation and the sequence becomes obvious:

Convert a raw score into a z-score using z = (x − μ) / σ, plus the two-tailed p-value from the standard normal distribution.

When to use this calculadora

Z-Score calculadora is aimed at people arriving with questions like these:

  • "Z score formula"
  • "Normal distribution table"
  • "P value from z"
  • "What is z score"
  • "How to calculate z score"
  • "Z score example"

When to reach for something else

Every tool has an edge where it stops being the right answer. Z-Score calculadora is no exception:

  • For legally binding tax or medical decisions — cross-check with HMRC, NHS or a qualified professional.
  • For very large or very small extremes the rounding error outgrows the useful precision.
  • When the underlying rate or threshold has changed since the page was last reviewed — always verify with the primary source.
  • When the input you have is already a derived figure (net of something) — feeding it in as "gross" will double-subtract.

Traps to steer around

Every time you crunch the numbers for a new scenario, one of these creeps in — it's worth knowing them ahead of time.

  • Ignoring the unit multiplier (k, M, %, basis points) on the input and feeding the raw number in anyway.
  • Assuming the default settings match your context — check the calc's assumptions box before trusting the figure.
  • Re-entering the result of a previous step as an input without keeping the full-precision number in front of you.
  • Reading a negative answer as an error when the maths is telling you the inputs are in the wrong order.
  • Cross-comparing to a tool that uses a different formula family (e.g. Mifflin vs Harris-Benedict) without saying so.

The sources behind the numbers

Where the maths needs an external authority, we cross-check against:

  • NIST
  • Khan Academy

Works well alongside

If this question keeps coming up for you, the same cluster of tools usually comes next:

  • Standard Deviation Calculator — Measure the spread of a data set with sample or population standard deviation.
  • Mean (Average) Calculator — Add up your values and divide by how many there are — we show each step.
  • Confidence Interval calculadora — Work out 90%, 95% or 99% confidence intervals for a mean or proportion, with sample-size guidance and margin of error shown.
  • Binomial Distribution calculadora — Compute binomial probabilities P(X=k), P(X≤k) and P(X≥k) for n trials with success probability p — with mean np and variance np(1−p).

How we keep this accurate

Our calculadoras run on pure, unit-tested functions — the same logic lives in the browser and in the CI test suite. When tax rates, thresholds or official figures move, the update lands within 24 hours of the announcement. You can read the editorial policy and corrections policy.

Found an out-of-date number on Z-Score calculadora or anywhere else in the Maths toolkit? Send it to the editorial desk and we'll patch it. Or browse the full calculadora directory for the next tool you need.

Frequently asked questions

Z score formula?
Tldr: feed the figures into the Z-Score calculadora widget and it'll show the working. Convert a raw score into a z-score using z = (x − μ) / σ, plus the two-tailed p-value from the standard normal distribution.
Normal distribution table?
The useful way to think about it: open the Z-Score calculadora widget at the top of the page. Convert a raw score into a z-score using z = (x − μ) / σ, plus the two-tailed p-value from the standard normal distribution.
P value from z?
Cutting to it, this question usually arrives alongside Standard Deviation Calculator, Mean (Average) Calculator, Confidence Interval calculadora. The Z-Score calculadora handles the specific case above; the others cover adjacent ground.
What is z score?
Short answer: every figure is cross-checked against NIST and the wider data. If you notice a stale rate, email the editorial desk and we'll patch it in under 24 hours.
How to calculate z score?
Quick version: yes, everything runs in your browser. No inputs are sent to our servers or any third party, nothing is logged and nothing persists after you close the tab.
Z score example?
Practically speaking, Z-Score calculadora is free to use, free to share and free to embed — pass the URL around a class, a slack channel or a family chat. The editorial policy covers attribution.
Z score worked example?
Here's the plain-English summary: the short method: write the inputs in the units shown, run the calculation, then sense-check the answer against an order-of-magnitude estimate in your head.
Z score explained?
In one line: if the result surprises you, run it a second time with slightly different inputs — small swings often reveal a unit or rounding issue in the original figures.
Z score definition?
Put simply, a calculadora is a sanity check, not a verdict. For anything legally binding — contracts, tax filings, medical decisions — bring the figure to a qualified professional as a starting point.
Z score meaning?
The direct take: Convert a raw score into a z-score using z = (x − μ) / σ, plus the two-tailed p-value from the standard normal distribution. The page walks through the method in full so you can answer follow-up questions without guessing.
Z score step by step?
Straightforward answer: open the Z-Score calculadora widget at the top of the page. Convert a raw score into a z-score using z = (x − μ) / σ, plus the two-tailed p-value from the standard normal distribution.
Z score uk?
Without the jargon, open the Z-Score calculadora widget at the top of the page. Convert a raw score into a z-score using z = (x − μ) / σ, plus the two-tailed p-value from the standard normal distribution.

References

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