Enter X and Y
X in the first column, Y to the right; replicates side by side.
WAVESPEED AI LINEAR REGRESSION YOUR DATA STAYS ON YOUR DEVICE
100% FREE
Free Linear Regression CalculatorSlope, intercept and R² with confidence intervals.
Paste X and Y values (with replicates if you have them) to get the slope and intercept with standard errors and 95% confidence intervals, R², Sy.x and whether the slope differs from zero.
Read unknown samples off a standard curve, or try a quadratic or cubic and compare the fits.
Slope ± SEStandard curvesNo upload
No sign-up No upload No watermark
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Calculations run in your browser. Your data is not uploaded; the project is saved in this browser only.
THREE SIMPLE STEPS
How to use the Linear Regression Calculator
Fit the line
The straight line is fitted at once, with a confidence band. Choose a polynomial, a line through the origin or weighting if needed.
Use the result
Type absorbances to interpolate concentrations, copy the table, and save the graph.
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Linear Regression Calculator FAQ
What does R² mean?
The fraction of the variation in Y explained by the line. It does not say whether a straight line is the right model: check the residuals and the runs test.
Line or quadratic?
Choose “Compare with” to test whether a quadratic fits significantly better (F test and AICc).
Can I force the line through zero?
Yes: choose “Line through the origin” as the equation, or fix YIntercept at 0 under Constraints.
Is my data uploaded?
No. The regression runs in your browser.
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Slope ± SE · Standard curves · No upload