# Heatmap Generator Generate customizable heatmaps from data, perfect for visualizing data density, correlations, and patterns > Canonical page: https://elysiatools.com/en/tools/heatmap-generator - **Category:** Data Visualization - **Keywords:** heatmap, chart, graph, visualization, matrix, grid, density, correlation, pattern, color ## Overview The Heatmap Generator is a powerful data visualization tool that transforms raw numerical data into intuitive, color-coded heatmaps, making it easy to identify patterns, correlations, and density at a glance. ## Inputs - **Chart Data** (textarea): Data for the heatmap. Supports JSON object with rows/columns/data or CSV format - **Chart Title** (text): Title that will be displayed above the chart - **Color Scheme** (select): Select color scheme - **Custom Colors** (text): Custom color gradient (comma-separated hex colors, requires Custom scheme) - **Cell Size** (number): Size of each heatmap cell in pixels - **Cell Padding** (number): Padding between cells in pixels - **Min Value** (number): Minimum value for color scale (leave empty for auto) - **Max Value** (number): Maximum value for color scale (leave empty for auto) - **Background Color** (color): Background color for the chart container - **Show Values in Cells** (checkbox): Display values inside the heatmap cells - **Show Row/Column Labels** (checkbox): Display labels for rows and columns - **Round Values** (checkbox): Round values to whole numbers for display - **Show Color Scale** (checkbox): Display color scale legend below the chart ## When to use - When you need to visualize complex matrix data to identify trends or outliers. - When comparing performance metrics across multiple categories or time periods. - When you want to create professional-grade visual reports from CSV or JSON datasets. ## How it works - Input your data in either JSON format (with rows, columns, and data arrays) or CSV format. - Customize the appearance by selecting a color scheme, adjusting cell size, and toggling labels or values. - Set specific minimum and maximum values to define the color scale range for your data. - Generate and preview your interactive heatmap directly in your browser. ## Use cases - Analyzing website traffic patterns across different days of the week and hours. - Visualizing correlation matrices for financial or scientific research datasets. - Creating performance heatmaps for employee KPIs or sales team regional targets. ## Frequently asked questions ### What data formats are supported? The tool supports raw data input in either JSON object format or standard CSV format. ### Can I use my own colors? Yes, by selecting the 'Custom' color scheme, you can input a comma-separated list of hex color codes. ### Is it possible to hide the numerical values inside the cells? Yes, you can toggle the 'Show Values in Cells' checkbox to display or hide the data points. ### How do I define the range of the color scale? You can manually set the 'Min Value' and 'Max Value' fields to control the color intensity; otherwise, the tool will auto-calculate based on your data. ### Can I download the generated heatmap? 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