Linear Regression Calculator

Overview

This linear regression calculator fits a straight line to your data. You get the equation, slope, y intercept, correlation, and R squared. You also see a scatter plot with the best fit line drawn over your points. Use it for class, work, or a fast sense check.

How It Works

Enter pairs in the form x,y on separate lines. The calculator reads each line and keeps only valid numbers. It uses ordinary least squares to find the slope and the y intercept. It then computes the correlation coefficient r and R squared. The chart plots your points and the best fit line for quick review.

Input details

• Data input box: type one pair per line like 1,2
• Use one comma in each line only
• Use decimal points for fractions like 3.5
• Add at least two valid pairs

Output explained

• Equation: the line of best fit as y equals mx plus b
• Slope m: change in y for a one unit change in x
• Y intercept b: the value of y when x equals zero
• Correlation r: strength and direction between x and y
• R squared: share of variance in y explained by the line
• Count: number of pairs used in the fit

Reading the chart

• Orange dots show your data points
• The blue line shows the best fit line
• Axis labels help you read values at a glance

Step-by-Step Instructions

1. Paste or type your x,y pairs in the text box
2. Click Calculate to run the fit
3. Review the equation, r, and R squared
4. Check the chart for the trend and any outliers
5. Use the equation to estimate y for a new x

Benefits for Every User

You get clear math and a clean chart in seconds. The format is simple and quick to learn. Results update from your exact pairs, with no setup work. It works great for small data checks and fast reports.

Real-World Applications

• Homework checks for simple linear regression problems
• Sales trends by month with a straight line fit
• Growth versus spend for quick marketing checks
• Quality data pairs like length and weight
• Physics labs that expect a line and R squared

Final Thoughts

Clean data gives you better fits and clearer charts. Use at least two different x values, and add more for stability. Large outliers can shift the line, so review the dots on the chart. Keep units consistent across all pairs for sound results. If every x value matches, the slope makes no sense, so vary x. This linear regression calculator keeps the math simple and the output clear. Run it now, then use the line to make fast and honest calls.