Linear Regression Calculator
Fit a straight line to paired data. Enter x,y points (one per line) to get slope, intercept, equation, and R².
FAQ for this calculator
- What format for points?
- One pair per line: 1, 2 or 1 2—semicolons also separate lines.
- What is R²?
- Fraction of y variance explained by the line—1 means perfect linear fit.
- Vertical x values?
- All same x breaks the formula—need variation in x.
- Predict y for new x?
- Plug x into y = mx + b using the slope and intercept shown.
How to use the linear regression calculator
Least squares minimizes vertical distance from points to the line y = mx + b.
- List x,y pairs from your dataset.
- Tap Calculate regression.
- Use slope, intercept, and R² for analysis.
When to use this calculator
- Homework check for stats or algebra.
- Quick trend line on lab data.
- Scatter plot fit before charting in Excel.
Examples & walkthrough
- (1,2), (2,4), (3,5) → positive slope with R² under 1 if not perfectly linear.
- Perfect line (0,0), (1,2), (2,4) → slope 2, intercept 0, R² = 1.