# [Excel] How to make a simple gauge

A gauge with three states in a continuous scale. Useful for displaying simple KPIs in dashboards where screen real estate allows it.

### Design notes

• To create a gauge you need to transform your data points to polar coordinates using basic trigonometry.
• For a pointer, you also need a center and a radius.
• Use a scatterplot for x,y values.
• You need two new data points to create a continuous scale, or more, if you want to display classes.
• Set the lower slice to no fill to hide it and a gradient fill in the upper slice.
• Orange/blue are a safe bet for diverging colors. Check if the pair you chose is color blindness safe.
• The KPI value is usually displayed, as a label or below the chart.

### Video

• 00:25: Formula for the X column:

``````=COS(PI()*tblData[KPI])*Table7[Radius]
``````
• 00:38: Formula for the Y:

``````=SIN(PI()*tblData[KPI])*Table7[Radius]
``````
• 00:50: Select a scatterplot for the pointer.

• 01:35: Try to make the chart square.

• 01:50: You add the scale as a scatterplot, but that’s an intermediate step. After changing it to doughnut you nee to define the ranges again.

• 02:30: Invert the x-axis so that zero is on the left and 100% is on the right.