CompressResize Guides

Make better image decisions

Clear explanations, practical decision tables and tools you can use immediately. No recycled lists of settings and no promise that one format wins every time.

Our method

Advice that matches what browsers actually do

These guides distinguish between dimensions, file size, format and encoder quality. When a choice depends on the image itself, the guide says so and links to a local comparison instead of inventing a universal answer.

Compare your image

Start with the constraint

Choose a workflow by what must remain true

A file can fail because its dimensions are wrong, its byte size exceeds a limit, its format is rejected or its transparency disappears. Those are different problems. Before changing an image, identify the exact requirement and preserve what matters: readable text in a screenshot, natural detail in a photograph, a transparent logo or a strict upload limit.

For forms

Check format, maximum bytes and exact dimensions before compressing. A smaller file can still be invalid.

For websites

Match displayed dimensions, compare modern formats and avoid shipping pixels that the layout never shows.

For email

Prioritize compatibility and a practical attachment size while keeping the subject legible at normal zoom.

How these guides are maintained

Advice is checked against the browser workflows offered on this site using photographs, screenshots, graphics and transparent samples. Because encoders and source images differ, we publish decision rules and limitations rather than claiming one quality percentage works for every file. Read the editorial and testing policy for our review, privacy and correction process.