Short answer
Check the receiving website's file-size limit and accepted image format. In Just Converter Image tools, enter a slightly smaller Target size (KB), convert a copy and inspect the result. The app can reduce quality or dimensions to try to reach the target.
This guide covers Just Converter. Check requirements and download options before you begin.
On this page
File size and picture size are different
A limit in KB or MB describes how much storage the file uses. A limit such as 1200 × 800 pixels describes the picture's width and height. A website can require both, so check both before changing the image.
What you need
- The original picture and a copy to test.
- The website's maximum file size, accepted format and any minimum or maximum dimensions.
- A separate folder for the smaller copy.
Example: fit a 500,000-byte upload limit
Add one copied picture
Open Image tools and add the copy. Choose a separate output folder so the original stays available.
Choose an accepted format
JPG often suits photos. PNG can be better when sharp text or transparency matters, but it may be larger. Choose a format the receiving website accepts and keep Preserve aspect ratio selected unless it requires exact dimensions.
Enter a target with a little room
For a maximum of 500,000 bytes, enter 480 in Target size (KB). This app uses 1 KB = 1,024 bytes, so 480 KB requests 491,520 bytes. Choose Start operation, read Review before starting and choose Confirm and start. If the target cannot be reached, the app reports an error.
Check the saved copy
In File Explorer, right-click the result and open Properties. Compare Size in bytes, not Size on disk, with the website's limit. Open the picture at normal size and check its content before uploading it.
How the app tries to reach the target
The app tests quality settings and can reduce dimensions when needed. If its attempts cannot reach the requested size, it removes partial output and reports that the target is unreachable. It does not judge whether writing or other detail is still readable.
If the target fails or the picture looks worse
For an unreachable target, try smaller dimensions if the website allows them. You can also try another accepted format. If the result fits but small writing or faces become unclear, return to the original and use a less demanding target. A readable picture matters as well as its byte count.
If the website still rejects it, check its format and dimension rules. A smaller file alone will not fix the wrong format or the wrong pixel dimensions.
When you only need a smaller file in the same format
A format change and a file-size change are different tasks. For a smaller copy that stays in the same supported format, see Make Smaller. For a PDF upload limit, use the PDF compression guide.
Check before using the image
- Size in bytes is below the actual limit, and the receiving website accepts the format and dimensions.
- Small writing, faces and edges remain clear enough for the task.
- The original is still available if you need a different result.