Free tool
Scatter Plot Maker with Trend Lines, Groups and Log Axes
Paste two columns of numbers and the plot is drawn as you type. Add a trend line to see the equation and R squared, split the points into groups, and save the picture for a report or a slide.
Paste columns straight from a spreadsheet, or separate numbers with a tab, comma, semicolon or space. A text column after y names the group. A first row of names is used for the axis titles.
Trend line
Axes
Points and colours
The plot is drawn in your browser and your numbers are never uploaded. They are kept on this computer for next time, unless the data is very large.
From a spreadsheet column to a chart in one paste
A marketing report often needs one picture that answers one question: does more of this go with more of that. Ad spend and sign-ups, page weight and bounce rate, hours of training and test score. A scatter plot answers it, and this page lets you skip the chart wizard.
Copy two columns from your sheet and paste them into the data box. Numbers can be split by a tab, a comma, a semicolon or a space. If the first row is text, it is used for the axis titles. A third column holding text, such as a group name, puts each group in its own colour. Open a CSV file loads a file instead, and the Examples buttons load a one-group, a two-group and a curved sample so you can see the format.
Numbers such as 1,250, $1,250.50 and 45% are all read as numbers.
Reading the trend line
| Fit | Use it when |
|---|---|
| None | You only want the points |
| Straight line | The points drift up or down at a steady rate |
| Curve, degree 2 | The points bend once, like a bowl or a hill |
| Curve, degree 3 | The points bend twice, with an S shape |
The straight line is a least squares fit. Tick Show the equation and R² on the chart to print the formula and R squared beside the line, and the same numbers also appear in a table under the plot. R squared runs from 0 to 1 and tells you how closely the points follow the line, but a high value does not prove one thing causes the other.
With groups, One trend line for each group draws a line and an equation per colour.
Axes, points and colours
- Titles and ranges. Name each axis, or set the start and end of x and y by hand if the automatic range hides something.
- Log scale. Switch either axis to a log scale when values span several orders of magnitude, such as page views.
- Points. Choose Small to Extra large, give each group a different shape, or join the points with a line.
- Colours. Violet, Bright, Calm or Greys. The Greys set works when the chart will be printed in black and white.
- Background. White, Dark or See-through for placing on a slide.
Save PNG, SVG and PDF give you a file, and Copy picture puts the plot on the clipboard for pasting into a document.
Making a chart that tells the truth
A few habits keep a scatter plot honest.
- Start the axes where the data makes sense and say so in the axis title. A cropped axis can make a weak link look strong.
- Do not draw a curve of degree 3 through ten points and call it a finding. More bends always fit better, and fit is not the same as understanding.
- Look for outliers before you fit a line. One strange point can drag a straight line away from the rest.
- Keep group colours the same across all the charts in one report.
If the chart is for a landing page test, pair it with the test details. Our guide on website conversion optimization covers which numbers are worth looking at in the first place.
Frequently asked questions
How do I paste data from Excel or Google Sheets?
Select the two columns, copy them, and paste into the data box. Spreadsheet columns arrive separated by tabs, which the tool reads directly.
How do I show more than one group?
Add a third column that holds a group name for each row. Each name gets its own colour, and you can ask for a separate trend line for each.
What does R squared mean?
It is a number from 0 to 1 that shows how closely the points follow the fitted line. A value near 1 means a close fit, though it says nothing about cause.
Can I use a log scale?
Yes. There are separate tick boxes for the x axis and the y axis. Log scales suit data that grows by multiples.
Can I use the chart in a slide or report?
Yes. Save it as a PNG, SVG or PDF, or copy the picture. The See-through background option helps on coloured slides.
Are my numbers stored anywhere?
They stay in your browser. The data is remembered on this computer for next time, and nothing is sent to a server.
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