Medium displays featured images at approximately 1400x788 pixels (16:9 ratio) for the best presentation in feeds and article headers. Inline images display at the article width of approximately 700 pixels.
For the sharpest display on Medium, upload featured images at 1400x788 or larger. Medium will resize down as needed. For inline content images, 700-1000px wide provides excellent quality without excessive file sizes.
Medium compresses uploaded images, so starting with good quality is important. Upload at 85-90% JPEG quality or PNG for graphics. Medium accepts JPEG, PNG, and GIF formats.
With ImgTools, resize your article images to the recommended dimensions. Use 1400x788 for featured images and 800px wide for inline content images (slightly larger than display width for retina sharpness).
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