How do you resize an image online?
To resize an image online, upload your file, choose a target width or reduction percentage, keep the aspect ratio locked, then download the resized image.
Explanation
The easiest method is to start from a target width. For example, a web article image can often be reduced to 1200 or 1600 px wide. With the aspect ratio locked, the matching height is calculated automatically and the image is not distorted. Percentage resizing is also useful when you want to quickly shrink a whole batch of photos.
Formula / method
New height = new width ÷ aspect ratio
Aspect ratio = original width ÷ original height
Concrete example
A 4000 × 3000 px photo has a 4:3 ratio. If you choose a width of 1200 px, the correct height is 900 px. The final image is 1200 × 900 px.
Common mistake
The most common mistake is changing width and height separately without keeping the ratio. The result can look stretched or squashed.
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