Type or paste one x, y pair per line. The axes are scaled to round numbers. Turn on the trend line to see the best-fit equation and R². Nothing is uploaded.
Separate x and y with a comma, semicolon, tab or space. A first line with names is skipped. Up to 500 points.
Best fit: y = 5.226x + 46.86 · R² = 0.9706
Each axis is rounded outward to a step of 1, 2 or 5 times a power of ten. The best-fit line is y = a·x + b with a = Sxy / Sxx and b = mean y − a · mean x. R² = Sxy² / (Sxx · Syy).
For (1,2), (2,4), (3,5), (4,4), (5,5): mean x = 3, mean y = 4, Sxy = 6, Sxx = 10, Syy = 6. The slope is 0.6, the intercept 2.2 and R² = 36 / 60 = 0.6.
It is the least-squares line: the slope is the sum of (x − mean x)(y − mean y) divided by the sum of (x − mean x)², and the line passes through the point of the two means.
R² is the share of the variation in y that the straight line accounts for, from 0 to 1. A value near 1 means the points lie close to the line. It does not show that x causes y.
The line needs at least two different x values. If every x is the same, the line is not defined.
Yes. Two columns copied from a spreadsheet are separated by a tab, which the tool accepts.