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Dynamic Matrix Heatmap — a Power BI custom visual by TCViz · Version 1.0.0.0 · Last updated: 3 August 2026

Dynamic Matrix Heatmap lets the people reading your report choose their own crosstab. Instead of you building one matrix per combination, they pick the X dimension, the Y dimension and the value from dropdowns inside the visual — no edit rights, no request to a developer.

Video walkthrough

Quick start

Drop the visual on the canvas.
Drag two or more fields into Dimensions. These populate the X and Y dropdowns.
Drag at least one measure into Measures.
In the visual, pick an X axis and a Y axis. The matrix appears.
Optional: drag a raw ID column (such as customer_id) into Distinct count of Pro to count unique values exactly.

Field wells

Well	Accepts	Limit	Purpose
Dimensions	Any grouping field	3 Free / 10 Pro	Populates the X and Y dropdowns. Keep cardinality around 20–25 values per field.
Measures	Measures or numeric columns	2 Free / 5 Pro	Values shown in the cells.
Distinct count of	Raw ID columns	3 Pro	The visual counts unique values itself, so the result is exact for every X/Y combination.

Why distinct counts are different here

Power BI computes a measure at the granularity of all the fields in the visual. When you display only two of them, the other values have to be combined. Sums, minimums, maximums and counts recombine exactly — but a distinct count does not, because a customer appearing under two different pickings would be counted twice.

That is what the Distinct count of well solves: give the visual the raw ID column and it counts unique values itself, in memory, for whichever pair of dimensions is on screen. The grand total matches your card visual exactly.

Format pane

Card	Setting	What it does
Values	Aggregation	How rows sharing a cell are combined. Auto reads what Power BI applied to the field; override it for DAX measures, where the aggregation is not readable.
	Show value as Pro	Absolute, % of row, % of column, % of grand total.
	Number format	Auto uses the model's format. Override when the model format is wrong for what is shown.
	Show totals Pro	Adds a total row and column, with exact distinct counts in the margins.
Heatmap colors	Minimum / Middle / Maximum	Three-point colour scale, applied globally across every visible cell.
Empty cells	Display as	Blank, dash, zero or grey fill.
Text	Axis labels, values	Font, size and colour, set separately.
Text	Controls bar	Background colour and label font for the dropdown bar.
Layout	Row height	Minimum row height in pixels.
	Column width	Column width in pixels.
	Column header orientation	Horizontal, vertical (90°) or diagonal (45°).

Interaction

Click a cell — filters the rest of the page to that X/Y intersection.
Click it again — clears the filter.
Ctrl / Cmd + click — adds cells to the selection.
Right click — the standard Power BI menu (Include, Exclude, Drill through).
Tab and Enter — keyboard navigation across cells.

Troubleshooting

The values do not match my card visual

If you are showing a count of something that can appear in more than one category, use the Distinct count of well with the raw ID column rather than a DAX measure. A distinct count computed at a finer grain cannot be recombined correctly by any client.

A field shows as a percentage when it should not

This happens when the same field is added twice, once normally and once with "Show value as → Percent of grand total": Power BI marks the underlying column as a percentage and the mark reaches both instances. The visual detects and corrects this automatically. If it persists, set Values → Number format → Number, and check the column's format in your model.

An average behaves like a sum

Set Values → Aggregation → Average. Auto-detection reads the field's label and query name, but a DAX measure carries its aggregation inside the DAX where it cannot be read.

"Showing a partial dataset"

The row limit was reached. The visual loads row-level detail in segments to keep distinct counts exact; with many dimensions at once the combinations exceed what Power BI will deliver. Remove a dimension or two.

Clicking a cell does not filter another table

Check the relationship between the tables in Model view. Filtering from a fact table to a dimension table needs the cross-filter direction set to Both.

Pro features are greyed out after purchasing

Sign out and back into Power BI to refresh entitlement, then reopen the report. If it persists, open an issue with your AppSource order reference.

Limits and known behaviour

Up to 25 distinct values are shown per axis; beyond that, the rest are omitted.
Average is an unweighted approximation when extra dimensions are loaded. Sum, minimum, maximum and count are exact.
With distinct counts, percentages of a row need not add to 100 — an entity present in several columns is counted in each. That is inherent to distinct counting, not a defect.

Getting help

Report a bug or request a feature
Changelog
Licensing questions: tinocallarisa@gmail.com