Linear Regression Calculator

Fit a best-fit line through up to four points.

x₁

y₁

x₂

y₂

x₃

y₃

x₄

y₄

Best-fit line y = 1.9x + 0

Slope 1.9

Intercept 0

R² 0.9627

Formula: least squares: slope = Σ(x−x̄)(y−ȳ) ÷ Σ(x−x̄)²

Step-by-step with your numbers:

1. Values used:

2. x₁ = 1

3. y₁ = 2

4. x₂ = 2

5. y₂ = 4

6. x₃ = 3

7. y₃ = 5

8. x₄ = 4

9. y₄ = 8

10.

11. Best-fit line = y = 1.9x + 0

12. Slope = 1.9

13. Intercept = 0

14. R² = 0.9627

Did we solve your problem today?

Find the least-squares line of best fit through your data points.

The math behind it

slope = Σ(x−x̄)(y−ȳ) ÷ Σ(x−x̄)²; intercept = ȳ − slope×x̄; R² measures fit quality.

Sample points → y ≈ 1.9x + 0 (R² ≈ 0.92).

R²?

The fraction of variance in y explained by x (0–1).