X axis
Y axis (left)
Dual Y axis (right axis)
Add a second Y axis on the right side of the chart to plot a series on a different scale. This is useful for combining measures with different units or magnitudes — for example, showing order count on the left axis and average order value on the right. To use the right axis:- In the Series configuration for a specific series, change the Y axis assignment from Left to Right.
- The right axis settings appear in the Style tab — configure its title, labels, and scale independently from the left axis.
Reference lines
Add horizontal reference lines to mark a target, threshold, or benchmark value. Reference lines appear at a fixed Y value across the full width of the chart. To add a reference line:- In the Y axis section of the Style tab, click Add reference line.
- Set the Value — the Y position of the line.
- Optionally set a Label that appears next to the line.
- Configure Color and Style (solid, dashed, or dotted).
Reference line labels
A reference line with no label renders as a bare rule — the reader has to already know what it means. Type text into Label to name it, for exampleTarget 18k.
Once a label is set, two alignment controls appear next to it:
New labels start at End and Above — the right end of the line, clear of the bars. The label
takes the line’s color, so it always reads as part of that line. Clearing the label removes the text
and leaves the line itself untouched.
Reference lines are only available on the left Y axis. For right-axis reference lines, use a custom Vega-Lite spec.