How it works
correlation calculadora — the short version
We built Correlation calculadora (Pearson r) because the other tools for this job either cost a subscription or came with a consent banner the size of a small novel.
Getting the arithmetic right first time saves a re-do on paper. Write the formula at the top of the page — then crunch the numbers and the rest of this page explains what the answer means.
Compute Pearson’s correlation coefficient r between two data sets, with strength, direction and coefficient of determination R² explained.
A worked example, step by step
Consider a realistic scenario and follow it through:
Compute Pearson’s correlation coefficient r between two data sets, with strength, direction and coefficient of determination R² explained.
Moments this tool earns its keep
Correlation calculadora (Pearson r) is aimed at people arriving with questions like these:
- "Pearson correlation formula"
- "R squared"
- "Correlation vs causation"
- "What is correlation"
- "How to calculate correlation"
- "Correlation formula"
Where the number stops being useful
Every tool has an edge where it stops being the right answer. Correlation calculadora (Pearson r) 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.
Five things that trip everyone up
Every time you crunch the numbers for a new scenario, one of these creeps in — it's worth knowing them ahead of time.
- Assuming the UK and US versions of the same unit are interchangeable — they're not.
- Typing a comma where the tool expects a dot (or vice versa).
- Rounding early — particularly painful in percentages and compound growth.
- Ignoring the time window: a 'per year' answer makes no sense with a monthly input.
- Treating the answer as private: screenshots are fine, but the URL always reruns cleanly.
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 calculadora — Measure the spread of a data set with sample or population standard deviation.
- Mean (Average) calculadora — Add up your values and divide by how many there are — we show each step.
- Z-Score calculadora — Convert a raw score into a z-score using z = (x − μ) / σ, plus the two-tailed p-value from the standard normal distribution.
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 Correlation calculadora (Pearson r) 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.