Hello KeyboardTools
Image tool

Heatmap Maker

Paste a rectangular CSV number grid to visualize ranges with a transparent min-to-max color rule and download a PNG.

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Enter comma-separated numeric rows. Red is high, blue is low, and the linear min-to-max scale is shown in each cell. Maximum 100,000 characters; processing stays local.

Download PNG

A QUICK WALKTHROUGH

How to use this tool

  1. Paste a rectangular CSV grid of finite numbers up to 100,000 characters.
  2. Choose Make heatmap.
  3. Review the labeled grid and download the PNG.

CSV grid and color scale

Rows must contain finite numeric values with equal column counts. The minimum is blue, the maximum is red, and intermediate values use a linear scale; values are printed in cells.

Local PNG export

Input is limited to 100,000 characters. The grid is drawn to a canvas and exported locally as PNG. CSV text is never inserted as HTML or uploaded.

GOOD TO KNOW

Common questions

How are colors chosen?

The smallest value is blue, the largest is red, and values between them use linear interpolation.

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