More pixels means more bytes
Camera phones write files with many millions of pixels, and every one of them has to be stored. A photo measuring 4000 by 3000 pixels holds 12 million values, which is why a single picture can weigh several megabytes straight out of the camera.
Resolution is the width and height of the image, and it is the factor you can change most decisively. Halving both dimensions leaves a quarter of the pixels, so the file shrinks sharply while the picture still looks fine at normal viewing sizes.
The format decides how each pixel is stored
JPEG throws away some information to stay small, while PNG keeps every pixel exactly and pays for it in bytes. The same photograph saved as PNG will be far larger than the same photo as JPEG, with no visible gain on a screen.
Screenshots and line art belong in PNG, because hard edges and flat colors are worth preserving. Photographs belong in JPEG or WebP. Files saved as BMP or TIFF are heavy by design, and Filekind accepts only JPEG, PNG, and static WebP, so those formats have to be saved as JPEG or PNG first.
Metadata is rarely the main cause
Photographs carry records of the camera, the settings, and sometimes the location. That information is real, but it is small compared with the pixel data, so stripping it alone will not turn a heavy file into a light one.
Treat metadata as a minor factor and resolution as the major one. If a file surprises you with its size, look at the dimensions first, because they explain the number far more often than anything stored alongside the picture.
Fix it by reducing pixels, then bytes
Resize the image to the size it will actually be displayed at, keeping the aspect ratio locked so nothing distorts. Fewer pixels give the compressor less data to work with, which is why resizing first makes a tight size target much easier to reach.
Then compress with the limit you need as the maximum. The tool works toward that number, verifies the final JPEG, and reports the output size, so you can see the result rather than guess at it.
- Resize to the display size when the image is far larger than needed
- Compress with a KB or MB target that matches the real limit
- Keep the original file somewhere safe for future edits
- Repeat one image at a time, since batch compression is not offered
What will not make a file smaller
Renaming the file or changing the letters after the dot changes nothing, because the image data inside is untouched. The same is true of copying it to a cloud folder or attaching it to a message: the bytes travel as they are.
This tool shrinks images, not documents. To make an existing PDF lighter, run it through Compress PDF; to keep a photo PDF light from the start, reduce the pictures, then generate the document again from the lighter versions.