Reviewed practical guide
How to use Create an image thumbnail and verify the result
Fits the image inside a maximum 400 × 400 pixel box without enlarging it.
Fits the image inside a maximum 400 × 400 pixel box without enlarging it. Confirm that a proportional, uncropped thumbnail suits the container where it will appear.
Practical example: Generate lightweight previews for cards in a catalogue. Post-process verification is part of the workflow: a successful download alone does not prove that the content is correct.
What result to expect
A copy up to 400 pixels wide and high in a compatible source format.