Compare business performance
Scan regions, products, teams, or periods to find clusters of high and low performance.
FigEditorBrowser-based data visualization tool
Heatmap Generator for CSV and Excel Data
Turn a labeled matrix into a readable color map. Compare exact values across rows and columns, switch color scales, and export SVG or PNG directly in your browser.
- No sign-up required
- Private browser-based rendering
- SVG, PNG, and CSV export
Precise Heatmap
Heatmap data
Heatmap data
Use the first row for column labels and the first cell of each remaining row for its row label.
Your table stays in this browser. Values are converted directly into SVG geometry; no image model receives the data.
Exact SVG preview
Matrix heatmap
Categories: 4 · Series: 4
Start with sample data
Create Matrix Heatmaps for Business and Scientific Data
Use a heatmap when the relationship between two categorical dimensions matters as much as each exact value.
Find website activity patterns
Map activity by hour, weekday, cohort, channel, or another repeated dimension.
Explore correlation matrices
Visualize relationships among research variables with positive and negative values around zero.
Summarize survey grids
Compare ratings across questions and groups while retaining the underlying scores.
Review learning outcomes
See performance across students, classes, assessments, or curriculum areas in one view.
Compare scientific measurements
Visualize expression values, experimental measurements, or coded observations across samples.
Make a Heatmap from CSV or Excel Data
Keep matrix input, color scale, exact values, preview, and export in one focused workspace.
Paste a complete labeled matrix
Copy rows with the header row and row labels intact.
Bring data from familiar tools
Upload CSV or XLSX files, or paste comma-, tab-, or semicolon-separated data from Excel, Google Sheets, CSV, or TSV.
Compare cells on one shared legend
Minimum and maximum values define a consistent scale across the full matrix.
Keep exact values visible
Show each numeric cell on top of its color whenever readers need precise lookup as well as pattern recognition.
Choose the scale that matches the data
Use sequential colors for magnitude, diverging colors around a midpoint, or perceptually even Viridis.
Export SVG or PNG
Save an editable vector for reports or a ready-to-share bitmap for documents and slides.
Why Use an Online Heatmap Maker
Move from raw matrix to presentation-ready visual without rebuilding the data in a full design application.
Stay tied to exact values
Every cell color is calculated deterministically from the visible numeric data.
See patterns immediately
The preview updates as soon as you paste or change the matrix.
Keep the precise workflow local
The browser-based chart renderer does not need to send the matrix to an image model.
Reuse a crisp vector
SVG export keeps text, cells, and legend sharp at document, slide, or poster size.
Make dense matrices scannable
Labels, values, contrast-aware text, and a shared legend keep the visual interpretable.
Match color to meaning
Switch palettes without re-entering the data or changing the matrix structure.
How to Create a Heatmap Online in 3 Steps
Paste a labeled matrix, choose a meaningful color scale, then export the heatmap you reviewed.
Paste a labeled matrix
STEP 1 Include column labels in the first row, row labels in the first column, and numeric values in the remaining cells.
Choose the palette and labels
STEP 2 Use a sequential, diverging, or Viridis scale and decide whether exact values should appear in every cell.
Review and download
STEP 3 Check the minimum, maximum, missing cells, labels, and legend before exporting SVG or PNG.
Matrix Heatmap vs Geographic and Attention Heatmaps
CHOOSE THE RIGHT VISUAL
Matrix heatmap
Choose this tool when repeated row and column categories should expose patterns across both dimensions.
Geographic heat map
Choose mapping software when addresses, boundaries, coordinates, or spatial density define the story.
Attention heatmap
Choose an eye-tracking or predictive-attention tool when you need to evaluate where viewers look in an image.
Simple pricing
Create more. Explain better.
Choose a plan designed for the way you communicate research.
Basic
$19$9.5/month
For individual researchers who need the complete visual workflow with a practical credit allowance
Start creating- 5,040 credits per year
- ≈ $0.18/image
- All scientific figure tools
- High-resolution PNG exports
- Commercial use included
Plus
$39$19.5/month
For researchers who need more iterations, commercial use, and every advanced visual workflow
Start creating- 12,960 credits per year
- ≈ $0.14/image
- All scientific figure tools
- High-resolution PNG exports
- Commercial use included
Enterprise
$69$34.5/month
For teams that need high-volume credits, commercial use, and support across the full workflow
Start creating- 28,800 credits per year
- ≈ $0.12/image
- All scientific figure tools
- High-resolution PNG exports
- Commercial use included
Frequently asked questions
How do I create a heatmap from Excel or CSV data?
Copy a rectangular matrix with column headers and row labels, then paste it into Heatmap Generator. Comma-, tab-, and semicolon-separated rows are supported. The preview calculates one shared color scale from the numeric cells, and you can export the result as SVG or PNG.
What data format does Heatmap Generator accept?
Use the first row for column labels, the first cell of every following row for a row label, and numeric values in the remaining cells. Keep the same number of cells in every row. Empty or nonnumeric cells are reported as missing instead of silently becoming zero.
Which heatmap color scale should I choose?
Use a sequential palette when values move from low to high, a diverging palette when positive and negative values should separate around a meaningful midpoint, and Viridis when you want a perceptually even scale that stays readable for many viewers.
Can a heatmap show exact values?
Turn on cell values to place each source number over its color. Contrast-aware text keeps labels readable against light and dark cells. For very large matrices, hide the numbers so readers can focus on the overall pattern, then provide the source table separately for precise lookup.
Can I make a correlation matrix heatmap?
Paste the same variable names across the header row and first column, followed by the correlation coefficients. Choose a diverging scale so negative and positive relationships separate around zero while the diagonal values remain visible. Review the coefficient range and labels before exporting the matrix.
Is this a geographic heat map generator?
This tool creates matrix heatmaps from labeled rows and columns; it does not place values on a geographic map. Use geographic mapping software when the analysis depends on addresses, boundaries, latitude, longitude, or spatial density. A matrix heatmap is better for comparing two categorical dimensions.
Can I edit or publish the exported heatmap?
Download SVG when you want editable vector text, cells, and legend, or choose PNG for immediate placement in a document or slide. Before publishing, compare every label, unit, palette meaning, minimum, and maximum with the source matrix, then add context for readers who cannot rely on color alone.
Does Heatmap Generator upload my data or require sign-up?
The precise heatmap workflow parses, summarizes, and renders the matrix locally in your browser without requiring an account. Your input is not sent to an image model. Avoid placing confidential identifiers in labels, and follow your organization’s data-handling requirements when storing or sharing exported charts.
Related chart tools
Create a Heatmap from Your Matrix
Paste the data, choose a color scale, and export an accurate SVG or PNG without signing up.
Heatmap Generator →