Raise an image file to an exact number of kilobytes — and work out what your current file size actually is, which is where most people get stuck.
How to check a file size in KB
Android
Open the photo in Google Photos, swipe up or tap the three-dot menu, and read the size under the filename. In the Files app, long-press the image and tap Details.
iPhone
Photos does not show file size directly. Open the Files app instead, or tap and hold the image in Photos, choose Share → Save to Files, then long-press it in Files and pick Get Info.
Windows
Right-click the file in Explorer and choose Properties. Read the Size line, not Size on disk — the second number is bigger and is not what a form measures.
Mac
Select the file in Finder and press Command + I.
KB, MB and the 1024 problem
One kilobyte is 1,024 bytes, not 1,000, and one megabyte is 1,024 KB. So a “1MB” limit is 1,024KB, and a file your phone calls 1.0MB may be 1,048KB — over the line. When you are close to a boundary, work in KB and give yourself a small margin.
Rounding is why uploads fail at exactly the limit. If a form allows 50KB, aim for 48–49KB rather than 50.0.
Why a file ends up too small
- WhatsApp. Images sent normally are recompressed hard, often down to 30–80KB. Ask the sender to attach it as a Document instead.
- Screenshots of photos. A screenshot captures your screen, not the original file, and throws away most of the resolution.
- Previous compression. Shrinking the file for a different form and then reusing it.
- Email preview downloads. Some clients save a reduced copy rather than the attachment.
In all four cases the pixels are already gone. A KB increaser gets the file past the validator, but if the portal also checks resolution you need the original image. Where possible, go back to the source.
Frequently asked questions
What is a KB increaser?
A tool that raises an image file to a larger size in kilobytes, so it clears a minimum size rule on an application form. It does this by re-encoding at higher quality and padding the file with data every image viewer ignores.
How do I increase a file from 10KB to 50KB?
Upload it above, type 50, and download. The result is exactly 50KB and looks identical to the original.
Does a KB increaser add real image detail?
Partly. Re-encoding at a higher quality setting genuinely restores some encoding detail. Beyond that the tool pads the file, which changes the byte count but not the picture. It cannot recover resolution that was thrown away earlier.