Correlation Coefficient Calculator
Pearson r for two data sets.
Enter your values
Enter the x values you are working with.
Enter the y values you are working with.
Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.
- Correlation r
- 0.91652
- R squared
- 0.84
- Strength
- strong positive
- Sample size
- 6
- Variance explained
- 84%
Quick answer
Pearson's r ranges from −1 to +1, measuring how closely two variables move together in a straight line.
r = Σ(x−x̄)(y−ȳ) / √(Σ(x−x̄)²Σ(y−ȳ)²)
At a glance
| What it does | Pearson r for two data sets. |
|---|---|
| Category | Statistics |
| Inputs needed | X values, Y values |
| Main output | Correlation r |
| Formula | r = Σ(x−x̄)(y−ȳ) / √(Σ(x−x̄)²Σ(y−ȳ)²) |
| Cost | Free — no sign-up, no download |
How to use the Correlation Coefficient Calculator
- 1Paste your X values separated by commas.
- 2Paste matching Y values in the same order.
- 3Read r and R².
Inputs explained
- X values
- Enter the x values you are working with.
- Y values
- Enter the y values you are working with.
Worked example
Using the values the calculator loads with:
Inputs
- X values1, 2, 3, 4, 5, 6
- Y values2, 4, 5, 4, 6, 8
Results
- Correlation r0.91652
- R squared0.84
- Strengthstrong positive
- Sample size6
- Variance explained84%
Frequently asked questions
Does correlation prove causation?
No — a third variable or coincidence can produce a strong r.
What is R squared?
The share of variance in Y explained by a linear fit on X.
What do I need to enter into the Correlation Coefficient Calculator?
Just 2 values: x values, y values. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.
How does the Correlation Coefficient Calculator work out the answer?
Pearson's r ranges from −1 to +1, measuring how closely two variables move together in a straight line. It applies the formula r = Σ(x−x̄)(y−ȳ) / √(Σ(x−x̄)²Σ(y−ȳ)²) and shows the working so you can check each step by hand.
Is the Correlation Coefficient Calculator free, and do I need an account?
It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.