Resize Image in KB (Reduce or Increase File Size)
Official forms, exam portals and job sites often require photos and signatures between a minimum and a maximum size, such as 20–50 KB. Enter the target and the tool reduces or increases the file size to meet it.
Runs in your browser
How to use
- Drop one or more images.
- Choose Reduce (at most) or Increase (at least).
- Enter the target size in KB or MB, or tap a preset.
- Download the result — its exact size is shown.
How it works
Reducing: the tool searches for the highest JPEG or WebP quality that stays under your limit. If even the lowest reasonable quality is too big, it gradually reduces the image dimensions until the file fits — so you get the best possible image within the limit.
Increasing: the image is first saved at maximum JPEG quality. If that is still below the minimum, the file is padded with a standard JPEG comment block. Comment blocks are ignored by every image viewer, so the picture looks exactly the same — only the file size grows to the required value.
Sizes use 1 KB = 1,024 bytes, as most upload forms do.
Examples
- Exam application
- Photo must be 20–50 KB → Reduce to at most 50 KB, then check it's above 20 KB.
- Signature scan too small
- A 9 KB signature must be at least 10 KB → Increase to 10 KB.
- Photo between 100 and 200 KB
- Reduce to at most 200 KB, then check the result: if it lands under 100 KB, raise the target slightly or start from a larger version of the photo.
Common uses
- Government and exam application forms
- Job portals with strict upload limits
- Email and messaging limits
Privacy & security
This tool runs entirely in your browser. Your files and text are never uploaded to our servers — processing happens on your device and results are created locally. How each tool handles files
Frequently asked questions
Does increasing the size improve quality?
No. Quality can't be added after the fact; the tool only makes the file meet a minimum size requirement.
Will the image be accepted as valid?
Yes — the output is a standard JPEG. The padding is a normal comment section defined in the JPEG standard.
Can I reach an exact number of KB?
Increasing reaches the target almost exactly; reducing gives the largest file under the limit.
The form still rejects my file.
Check the other requirements too: many portals also fix the dimensions (for example 600 × 800 px), the format (JPG only) and sometimes the colour mode. Resize the image to the required dimensions first, then bring it under the size limit.
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