Charts & Tables · Browser · Free
Line Graph Maker
Type labels and values for up to seven line series and Draw draws the chart right in your browser. Set the chart title, the horizontal and vertical axis titles, the number format, a linear or log scale for each axis and where the legend sits, then save the chart as a PNG.
What this line graph maker does
You give the chart a title, a title for the horizontal axis and a title for the vertical axis. Pick a number format for the value labels and choose a linear or a log scale for each axis on its own, so the two sides of the chart can be scaled differently.
Add between one and seven line series. Each series has a name, which is what the legend shows, and its own set of values. Choose where the legend sits. Press Draw to build the chart from what you entered, Save PNG to download it as an image, and Clear to go back to the sample data.
Entering labels and values
Data goes in as labels, as values, or as a range. Separate the values with spaces or with commas, one after another in the order they should be plotted.
Labels take one word, so an underscore in a label becomes a space. Writing yearly_sales shows up on the chart as yearly sales.
Reading the chart
The labels mark the positions along the horizontal axis, and each series is drawn as its own line through its values at those positions. The legend matches every line to its series name.
The vertical axis carries the values, shown in the number format you picked. On a linear scale, equal vertical distances mean equal changes in value. On a log scale, they mean equal ratios instead, which keeps values that differ hugely in size readable on one chart. A series that climbs at a steady rate reads as a straighter line on the log scale than on the linear one.
Linear and log scale formula
On a linear scale a value is placed in proportion to the value itself, that is (value - start) / (end - start) of the way up the axis between the ends of the range. Doubling a value doubles its distance from the starting line.
On a log scale the same placement uses the logarithm of the value instead of the value, that is (log(value) - log(start)) / (log(end) - log(start)). One equal vertical step then multiplies the value by the same factor as every other step, so a value of 10 sits one step above 1, 100 sits one step above 10, and so on.
A line looks straight between points that grow by the same ratio from one label to the next, and straight between points that grow by the same amount on a linear scale. Compare the two to see which kind of change the values follow.