About this visualization tool
Generate 2D matrix heatmaps from CSV or Excel data. Cross-tabulate category relationships, visualize numerical density, and export HD PNG or SVG images.
RJB World Visualization Tools
Heatmap Generator
Cross-tabulate two categorical variables and visualize matrix densities with interactive 2D heatmaps. Import your CSV data to highlight patterns, frequency clusters, and high-value zones.
Want the complete multi-format chart suite? Open Universal Data Visualization Studio
Upload your dataset
Drop your CSV, Excel (.xlsx/.xls), or JSON file here to visualize instantly
Or Paste CSV Data
Paste raw CSV or comma-separated rows below
Try Sample Datasets
Test chart features with 1-click sample data
Key Features & Capabilities
- •Cross-tabulation across X-axis and Y-axis categorical variables
- •Color intensity scaling proportional to cell values or frequency counts
- •Customizable color palettes and value label overlays
- •Handles missing grid combinations seamlessly
- •Export high-resolution PNG images or vector SVG graphics
Frequently Asked Questions
How does the heatmap color scaling work?
Cells are colored based on their relative magnitude between the minimum and maximum values in your matrix, with darker/richer shades indicating higher concentrations.
Can I show exact numbers inside heatmap cells?
Yes! Toggle 'Show Data Values' in Chart Settings to display value overlays inside every cell.
What file formats can I import?
You can upload .csv, .xlsx, .xls, .tsv, or .json files directly.