Heatmap CSV Data Visualizer
Create a heatmap from CSV data online. Visualize patterns across two categorical dimensions with color intensity. Upload your CSV and export as PNG.
CSV to Heatmap — Free Online Tool
A heatmap encodes a numeric value as color intensity across a two-dimensional grid of categories. It is ideal for spotting patterns in matrices — feature correlation tables, time × day activity grids, cohort analysis results.
Select an X column and a Y column (both categorical), and the tool counts occurrences at each (X, Y) intersection and encodes the count as a color. Upload a CSV with at least two categorical columns to get started.
Frequently asked questions
Can I use a custom numeric value instead of counts?
Currently the heatmap uses row count per cell. Support for a custom Z-value column is on the roadmap.
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