Resize an image to 300 KB
Three hundred kilobytes is seldom a form requirement. It usually comes up for a different reason: keeping a web page fast. It is a common rule of thumb for the largest image on a page, the one a visitor sees first, and that single image often decides how quickly the page feels like it has loaded.
No images yet. Add a photo and set the size you need.
Why website images get a size budget
A visitor on a slow mobile connection waits for your largest image before the page looks ready. Search engines measure that wait, and a slow page ranks lower than a fast one with the same content. A 2 MB photograph that could have been 250 KB with no visible difference is the most common cause of a page that feels sluggish, and it is also the easiest to fix.
Match the image to the space it fills
Decide how wide the image will actually appear, then size it to roughly twice that for sharpness on high-density screens, and no more. A photograph displayed eight hundred pixels wide needs around sixteen hundred pixels of image. Anything beyond that is downloaded and thrown away by the browser. Getting the dimensions right usually brings the file under 300 KB without touching the quality setting at all.
- A full-width banner: aim for 200 to 300 KB.
- An image inside an article: 100 KB or less is a better target.
- A thumbnail or avatar: under 30 KB.
- Photographs compress well. Screenshots and graphics with flat colour and sharp edges often do better as PNG or WebP.
If you are preparing many images for a site, the compressor handles a batch at a fixed quality in one pass, which is faster than setting a size for each one individually.
Steps
- Choose your image.
- The limit here is already set to 300 KB.
- Check the result at the size it will actually be displayed.
- Press Download.
Questions
Is 300 KB small enough for a web page?
For the single largest image on the page, yes. For images inside an article, aim lower — 100 KB or less — since several of them add up.
Should I use JPG or WebP for a website?
WebP is usually smaller at the same quality and every current browser supports it. JPG is the safer choice when a file also has to work with older software or be uploaded to a form.
How large should the image be in pixels?
About twice the width it will be displayed at. Beyond that the browser downloads detail it never shows.