Line Chart Maker

How to use Line Chart Maker

1. Enter your time points and values.
2. Label the axis clearly, especially if it does not start at zero.
3. Keep to a handful of series, highlighting the ones that matter.
4. Download the chart.
5. Unlike bars, lines need not start at zero — but the axis must be clearly labelled.
6. Use lines only where the x-axis has a meaningful order.
7. Break the line across missing data rather than interpolating silently.

The axis rule differs from bar charts

A line encodes position rather than length, so it does not have to start at zero — and often should not, because a stock price between 180 and 195 becomes a flat line on a zero-based axis and shows nothing. What matters is labelling the axis clearly so the reader sees the range. The honest test: would the reader draw a different conclusion if they saw the full range? If so, show it.

Use lines only for ordered data

The line between two points implies values exist in between and moved smoothly. That is true for time and for continuous variables, and false for categories — a line connecting sales by region suggests a journey from one region to the next that does not exist. Ordered categories such as age bands or satisfaction levels are a legitimate middle case. If the x-axis could be reordered without losing meaning, use bars.

Too many lines and nobody reads any of them

Four or five series is about the limit before a chart becomes a tangle. Beyond that, highlight the one or two that matter in colour and render the rest in light grey, which keeps the context and removes the noise. Direct labels at the end of each line beat a legend: a legend makes the reader match colours back and forth, and colour matching is exactly what some readers cannot do.

Gaps, and what a connected line claims

Connecting across missing data draws a line through values you do not have, which quietly asserts something false. Break the line at gaps, or mark interpolated sections visibly. The same applies to irregular intervals: plotting monthly and then yearly points at equal spacing distorts the shape of the trend, and the fix is to space the axis by actual time rather than by observation.