How to Compress a Photo to Under 100 KB on Android
Short answer: lower the JPG quality step by step until the file is just under 100 KB; if even low quality is too big, reduce the resolution a little and try again. Imgdeck does both automatically: pick 100 KB, pick the photos, tap Process.
What decides the file size
Two things: the number of pixels and the compression quality. A 4000×3000 photo has 12 million pixels; at high JPG quality that is several megabytes. Halving the width and height cuts the pixel count to a quarter.
Step by step
1. Open Imgdeck and tap Compress to KB. 2. Pick one or many photos. 3. Choose 100 KB (or 20, 50, 200 KB, or type a size). 4. Tap Process. Each photo is saved to Pictures/Imgdeck just under the limit, as sharp as the limit allows.
When the upload still fails
Some sites also require JPG only, or a minimum width. Use Convert format for JPG and Resize for pixel limits, then compress. Transparent PNGs keep transparency when compressed, but a site that requires JPG will need a solid background.
FAQ
Why is my phone photo 3–5 MB?
Modern cameras shoot 12–50 megapixels at high quality. A form usually needs a fraction of that.
Will 100 KB look blurry?
For a face or document at 1000–1600 px wide, 100 KB JPG is usually sharp enough on screen.
What if the site also limits pixel size?
Resize first (for example long side 1080 px), then compress to the KB limit.