How to Reduce Image Size to 100KB

Why the photo is so big

File size depends on two things: how many pixels the picture has, and how much detail is kept for each of them. A 12 megapixel phone photo has about 12 million pixels, so it weighs several MB. To reach 100 KB, one or both have to come down. Lowering the quality saves space with little visible change at first. Making the picture smaller in pixels saves much more, and is fine when the picture will only be seen on a screen.

How to reduce image size to 100 KB

1. Open Resize & Compress Image to 100KB.
2. Press Select photos and choose the picture from your gallery or files. You can pick several at once.
3. 100 KB is already selected. For 20, 30, 50 or 200 KB, tap that size, or type your own number under Other.
4. If the form also asks for a width and height in pixels, enter them as the maximum width and height.
5. Press Resize. Each picture shows the old and the new size.
6. Press Download, or Download all (ZIP) if you chose many.

Nothing is uploaded. The picture is processed on your phone or computer, which matters for photos of people and documents.

JPG, JPEG or PNG?

JPG and JPEG are the same format. It is the right choice for photos because it stores them in much less space. PNG keeps every pixel exactly, which makes photos very large, so a PNG photo is often several MB. The tool turns a PNG into a JPG to reach your size, and fills any transparent area with white. PNG is better for logos and screenshots with flat colours, but if a form asks for a small file, a JPG is the way to get there.

How to keep the picture clear

• Crop first. A close crop of the face or the document spends the size limit on what matters.
• Use a plain, light background. Plain areas compress well, a busy background eats the budget.
• Take the photo in good light. Dark, grainy photos compress badly and look blotchy when small.
• Do not resize twice. Start from the original, not from a copy that was already compressed.
• Choose the largest size the form allows. 100 KB looks better than 30 KB.

Smaller targets: 50, 30 and 20 KB

At 50 KB a face and a signature are usually still clear. At 30 KB and 20 KB the picture becomes small in pixels as well as lower in quality, because the quality alone cannot get a large photo that low. That is normal. If the result looks too soft, try a closer crop or a plain background before lowering the size again.

Is 100 KB 100,000 or 102,400 bytes?

Systems differ: some count 1 KB as 1000 bytes, others as 1024. The tool keeps the result under 100,000 bytes, so it passes either way. The size shown next to the picture uses 1024, so it may read a little lower, such as 97 KB.

If the form says the file must be between a minimum and a maximum size, such as 20 KB to 50 KB, choose a target a little under the maximum and check the size shown. The tool makes files smaller, it cannot make them bigger.