Guide
How to reduce image size to 100 KB, 500 KB or 1 MB
Published
To get an image under a size limit such as 100 KB, reduce its dimensions first, then lower the quality until the file size shown is under the limit. These two levers do most of the work: fewer pixels and stronger compression.
The free image resizer changes the dimensions and the image compressor changes the quality and format. Both run in your browser, so your photo is not uploaded.
Why file size is hard to predict
How small a file gets depends on the picture. A photo with lots of fine detail or noise compresses less than a flat graphic, and a 12-megapixel photo needs far more reduction than a 1-megapixel one. That is why no tool can promise an exact size from one setting. The practical method is to try, read the size, and adjust.
Step by step: get an image under your limit
- Open the image compressor and add your picture. It shows the original size.
- Press Process with the default quality and look at the new size shown next to the file name.
- If it is still too large, lower the quality slider (it goes from 10% to 100%) and process again.
- If a low quality already looks poor and the file is still too big, shrink the dimensions first with the image resizer, then compress the smaller image.
- Download the result when the size is under your limit and the picture still looks acceptable.
Choose the right format
Forms that ask for a size limit often name the accepted formats, so check before you convert.
- JPG suits photos and is accepted almost everywhere, including most upload forms.
- WebP often gives smaller files at similar quality, but check that the website or app you upload to accepts it.
- PNG keeps sharp edges and transparency, but photos saved as PNG are usually much larger.
Targets for 100 KB, 500 KB and 1 MB
These are starting points, not guarantees. The size shown after processing is the only reliable check. Also confirm the required dimensions in the form's instructions, since some forms set pixel sizes as well as file size.
- 100 KB: usually needs smaller dimensions and a lower quality. Passport-style photo uploads and form attachments commonly ask for this.
- 500 KB: often reachable by lowering quality alone on a typical phone photo, or by a modest resize.
- 1 MB: a medium quality setting is often enough, and a resize is only needed for very large photos.
Keep the picture looking good
For more on quality settings, read how to compress images without losing quality.
- Reduce quality gradually and stop as soon as the size fits.
- Resize before you compress rather than pushing quality very low.
- Keep your original file, and work on a copy.
- Do not enlarge a small image to get 'more quality'; it adds pixels but not detail.
Questions and answers
How do I reduce an image to 100 KB?
Resize it to smaller dimensions, then lower the quality in the image compressor until the size shown is under 100 KB.
Does the tool have a target file size option?
No. It has a quality slider, a format choice and a displayed result size, so you adjust and check. The resizer sets dimensions separately.
How do I reduce image size without losing quality?
Some loss is unavoidable when you shrink a file a lot. Resizing first and keeping quality as high as the limit allows gives the best result.
Is my image uploaded to a server?
No. Resizing and compression run in your browser.