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Image Histogram Viewer

Inspect the RGB and luminance histograms of any image — useful for exposure, contrast and colour-balance review.

100% in your browser — files never uploaded.
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RGB
Luminance
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How to use the Image Histogram Viewer

  1. 1
    Drop your image
    PNG, JPG, WebP.
  2. 2
    Read the chart
    Three RGB curves plus luminance.
  3. 3
    Refine
    Use the data to adjust exposure or colour balance in your editor.

About this tool

All processing happens in your browser via the Canvas API. No upload.

Image is downsampled to 800px max for fast computation; histogram shape is identical.

Frequently asked questions

Is it free?
Yes.
Are files uploaded?
No — every step runs in your browser.
What's luminance?
Rec. 709 weighted brightness: 0.21·R + 0.72·G + 0.07·B.
Why three curves?
Red, green and blue channels, additively blended.
Mobile-friendly?
Yes.

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