Image size & formats
Prepare a file within a minimum and maximum KB range
Understand a range such as 20–50 KB and why increasing bytes does not restore detail.
Read the range literally
If instructions say 20–50 KB, a 12 KB image may be too small even though it is below the maximum. Enter Minimum size 20, Maximum size 50 and Unit KB. If the instructions only say “under 50 KB,” leave the minimum blank.
What increasing size means
FormFile can add non-visual padding to JPEG files. The image can remain visually identical while its byte count increases. This is useful for a minimum-size rule, but it does not recover missing pixels or make blurred text readable. PNG and WebP do not receive the same minimum-padding treatment in this tool.
Review the result
Check the actual output size and the requirement status. If a format cannot meet the range, the status should guide your next step rather than the filename. Never rename a PNG to JPG to force acceptance.
A practical example
For a clear 14 KB JPEG that must be between 20 and 50 KB, keep its correct dimensions and set the range. For a blurry 14 KB image, obtain a better original before adding bytes.
Ready to prepare your file? Use Image size & dimensions and check the downloaded result.