Content:
1. Introduction to Heat Map
2. How to set up the Heat Map?
3. What's that telling us?
4. Controls for this chart - customize your view
You can find more information about the Analytics module in the dedicated article.
1. Introduction to Heat Map
The Heat Map is a graphical representation of data (in Kanbanize: cycle time) on a matrix that uses various shades of different colors in order to help distinguish the collected data in each cell of the matrix.
If you have to know which area needs the most attention, the heat map shows you that in a visual way, which is easy to assimilate.
The Heat map shows you where the most time gets accumulated. The red color always stands for higher time values.
- On the "x" axis is the actual workflow of the board (it reflects the workflow stages)
- On the "y" axis, you can choose different topics for example: type, assignee, priority, etc.
2. How to set up the Heat Map?
From the left side of the panel, you can control which data you can see on the chart within a predetermined time frame.
First, you select the workflows that you want to analyze. The graph takes into consideration all cards from the selected workflows. Note that you can add single or multiple workflows.
Second, you need to select at least one of the following fields: "Created At", "Start Date" or "End Date" and configure their value.
Note: you can't run the analysis without selecting at least one of the 3 fields. You can also select more than one of them for a more precise configuration of the dataset.
In addition, you can apply card filters (Add cards filter). For example, you may want to see only cards with high priority or cards that are of a certain type or size.
Once you have defined the workflow, you should select a topic from the Controls menu.
For example - a priority. 
3. What's that telling us?
Let's use the priority in the example below.
The heat map shows in which part of the workflow, the cards of high, critical, average priority spend the most time in the columns (in days). The graph accumulates the total number of days that the cards of certain priority spend in each of your workflow stages.
If there is an intersection on the Heat map colored in red, it signals that the cycle time of the tasks there is longer and that stage of your process needs attention. This visualization helps you easily find out the slowest part of the workflow and it is a good way to visualize bottlenecks.
In the example below, the cards with average priority take the most time in the Development/Coding column. If you click on any of the intersections, the system provides a list with all cards that have passed through that stage, so you can check the reasons for deviation easily. 
Hover on any Card ID to open the respective "Work Item Details" box. It contains specific information relevant to the card. In addition, you can check the time this card has spent in every stage of the workflow. 
Important:
The analytics use one calendar day as the lowest possible time unit.
For example: The card was created 30 minutes ago and was moved to "In progress". The system shows 1 day for this card.
The card was created late yesterday at 23:00 P.M. and you take a look at the chart in the morning at 9:00 A.M. (i.e. around 10 hours after the creation). The system will show 2 days as the card has been created yesterday and is still being worked on Today.
The Calendar time unit is used for analytics due to the fact that most of the modern Kanban systems are driven by client requests. As such, clients expect exact delivery dates or ranges that are calendar-based. They do not care about holidays, working hours, man-days, cycle, and lead times.
That being said, the Cycle Time Heatmap allows for recalculation based on working days.
Note: that the X axis (where applicable) would still display all calendar days/weeks.
The selection of working days recalculates the cycle time for all cards shown in the graph, but they do not change their position in time. Let's say we have a card that was moved to ‘In Progress’ on a Wednesday e.g. 06.01.2021 and was completed on Saturday 09.01.2021 and the team is working from Monday to Friday.
If no working days option is selected, the card's cycle time would be calculated as 4 days.
If working days are selected (Mon-Fri) for the Cycle time Heatmap, the cycle time for the example card above would be recalculated for each column that the card spent time in, outside of the working days. For example, if a card was in the 'Coding' column before the weekend, then with the exclusion of the weekends the number for the Coding column for a given user (when the Y axis is set to assignee) will be calculated for the 3 working days only (Wednesday, Thursday, Friday).
In case that you need precise cycle and log times for internal reporting, use the Advanced search capabilities with the different charts views and widgets.
4. Controls for this chart - customize your view
You can use the controls to change the "Heat Map" view as well as to apply additional filters. Please, check the short video below.
- Topic - select a property to change the values represented in the Heat map on the "y" axis.
By default, this will be set to 'Lane'. - Calculate Cycle Time by - this setting allows you to toggle between showing the Total days spent in each workflow stage or to display the Average Cycle Time for work items displayed on the chart. In addition, you can use the 50, 70, 85 and 95 percentile options for further aggregation.
- Color Palette - the heat map uses a warm-to-cool color spectrum to show you which parts of your workflow need more attention.
- Show/hide data control that allows you to zoom in and out of a specific interval within the selected time frame.
- Item Filter - allows you to further refine the data that you want to be displayed on the Heat Map.
- Workflow Stages - deselect the columns in your workflow that you do not want to be visualized on the "x" axis.
