How do I make a heatmap?

Describe the variables on each axis and what the color represents, then click Generate. For example: "A 5x5 correlation matrix for temperature, humidity, pressure, wind speed, and rainfall, with values in each cell and a blue-to-red scale." Figviz builds the grid, fills in the colors, and adds the legend automatically.

Is the heatmap generator free?

Yes. Every Figviz account starts with free credits you can use right away. Purchasing any pay-as-you-go credit pack removes the watermark and unlocks higher export resolutions up to 4K. Credits never expire.

What is a correlation heatmap?

A correlation heatmap is a special type of heatmap where each cell shows the statistical correlation between two variables, typically on a scale from -1 to 1. A diverging color scale (blue for negative, white for near zero, red for positive) lets you spot which pairs of variables are strongly related at a glance. It is widely used in data analysis, machine learning feature selection, and scientific research.

How do I choose the right color scale for my heatmap?

Use a diverging scale (blue to white to red) when your data has a meaningful midpoint such as zero or no change. Use a sequential scale (light to dark of one hue) for data that only runs in one direction, such as counts or sales totals. For accessibility, prefer colorblind-friendly palettes. Always include a labeled legend so readers can convert a shade back to a number.

Can I use heatmaps for data analysis and reports?

Yes. Heatmaps are a standard tool in exploratory data analysis, business reporting, and academic research. Figviz exports high-resolution PNG files suitable for slides, papers, and dashboards. Diagrams generated on a paid account can be used in your own professional or commercial materials.

AI-Powered

Heatmap Generator Heatmaps

Describe your data and get a clean, labeled heatmap chart in seconds. Axis labels, color-scale legend, and cell values included. Correlation matrices, calendar activity maps, confusion matrices, and more.

Last updated: 2026-06-21

✓Color-scale legend included✓Axis labels and cell values✓Correlation and calendar maps✓Download in 4K

Heatmap Generator

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Heatmap Examples

Browse heatmaps made with Figviz, or generate your own above

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Correlation Matrix Heatmap

A 5x5 correlation matrix with cell values and a diverging color scale from -1 to 1.

correlationmatrixstatistics

Calendar Activity Heatmap

A full-year calendar heatmap with daily cells shaded by activity count and a color legend.

calendaractivitytime series

Grid Data Heatmap with Color Legend

A general-purpose grid heatmap with categorical axes, cell values displayed, and a color-scale legend.

griddatacolor scale

Geographic Intensity Grid Heatmap

A geographic-style grid heatmap showing regional intensity values with latitude and longitude axes.

geographicintensityspatial

Confusion Matrix Heatmap

A 4x4 confusion matrix with predicted versus actual labels, cell counts, and a blue sequential color scale.

confusion matrixmachine learningclassification

Sales by Month and Region Heatmap

A 5-region by 12-month sales heatmap with dollar values in each cell and a sequential green scale.

salesbusinessmonthly

What is a heatmap generator?

A heatmap generator is a tool that turns grid-based data into a color-coded chart where intensity, frequency, or magnitude is represented by color rather than height or size. Cells with higher values get a warmer or darker color, making patterns, clusters, and outliers immediately visible to the eye. Figviz builds the grid, applies the color scale, adds the legend, and labels both axes from a plain description of your data, so you do not need spreadsheet software or a charting library to get a publication-ready result.

How to make a heatmap

Describe the variables on each axis and what the color intensity should represent (for example correlation, frequency, or revenue).

Say how many rows and columns you need and give example values or ranges if you have them.

Choose a style: Classic for a standard blue-to-red diverging scale, Colorful for a vivid multi-hue scheme, or Minimal for a clean sequential palette.

Set the aspect ratio and quality, then click Generate Heatmap.

Read the color-scale legend to interpret cell values, and refine your prompt if any labels or ranges need adjusting.

When to use a heatmap

Heatmaps are best when you have two categorical or ordinal axes and a numeric value at each intersection. Correlation matrices use them to reveal which variables move together. Calendar heatmaps show activity streaks and seasonal patterns at a glance. Confusion matrices in machine learning use them to highlight where a classifier makes systematic errors. Sales-by-region-and-month grids use them to surface high and low performers without scrolling through rows of numbers. If your goal is to spot spatial or relational patterns quickly, a heatmap is usually the right chart type.

Tips for choosing a color scale

Use a diverging scale (for example blue to white to red) when your data has a meaningful midpoint such as zero correlation or no change. Use a sequential scale (light to dark of one hue) when all values run in one direction, such as counts or sales figures that are always positive. Avoid rainbow scales for analytical work because they introduce false perceptual boundaries. Always include a labeled color-scale legend so readers can map a shade back to a number. For accessibility, consider colorblind-friendly palettes like blue-to-orange or viridis.

Frequently asked questions

A heatmap generator is a tool that converts grid-based data into a color-coded chart. With Figviz you describe your data in plain language and the AI draws a labeled heatmap with axis ticks, cell values, and a color-scale legend in seconds, without needing any charting library or spreadsheet.

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