Mixed charts are great for following and visualising trends in data when looking at 2 different Measures/values that aren't in a similar value range. For example, the total deposit amount and actives value per month.

How to use it

For a mixed chart, you can use a maximum of 2 Measures and 1 Dimension. A Time Dimension is specifically recommended.
In comparison to a bar chart, the 2 Measures don't necessarily have to be in a similar value range. In other words, the 2 Measures don't have to be similar to each other.

Example

A mixed chart has 2 y-axes
A mixed chart has 2 y-axes
In the mixed chart above, we can see the first Measure [Actives] being represented by the pink line corresponding to the numbers found on the y-axis to the left. The second Measure [Deposit Amount] is instead represented by the blue bars that correspond to the numbers found on the y-axis on the right side. The Time Dimension, [Date] grouped by month from the previous year, is represented in the x-axis.
In the chart, we can easily follow the monthly trends for 2 different Measures (actives and total deposit amount), even though they have completely different value ranges.
🙋‍ Note:
Whichever Measure is entered first will be represented by the line and the corresponding values will be found on the left y-axis.
The second added Measure will always be represented by the bars and will correspond to the y-axis found on the right side instead.

Mixed chart vs Bar chart

As recommended with a bar chart, in comparison with a mixed chart, the values of the Measures should be in the same value range for it to render nicely.
Below, we have the same Measures and Dimensions as we have in the mixed chart from the previous section.
Due to the value ranges being completely different for our 2 Measures, we can barely see any variety of values for the [Actives] Measure. Whilst with the mixed chart, we can easily distinguish the variance of the value for [Actives] for each month.
This really shows how important it is to select the correct Chart Type for your Widgets.