How to Compress Images to a Target File Size

1.Target a file size instead of guessing quality

A quality slider of 80 does not mean the same number of kilobytes for every photograph. A flat screenshot can already be small, while a detailed product photo stays large at the same setting.

Target-size compression treats the limit as a maximum goal. PixelShift tries several quality levels and keeps the largest result that still fits. If even the lowest quality stays above the limit, it returns that smallest file and warns you that the target was not reached.

2.Compress images in the browser

1. Open PixelShift Compress Image and drop one image or a batch onto the page. JPG, PNG, WebP, AVIF, SVG, and HEIC are accepted, up to 50 MB per file.
2. Choose an output of JPG, WebP, or AVIF. PNG is not offered here because a lossless PNG cannot be tuned down to a kilobyte target.
3. Pick 100 KB, 200 KB, 500 KB, or 1 MB, or type a custom target between 10 KB and 50,000 KB.
4. Select Compress Images. Each file is encoded locally, and the page shows how much smaller the finished batch is.
5. Download a single result or a ZIP. Image bytes stay on this device; they are not sent to a PixelShift conversion server.

3.Compression keeps the pixel dimensions

This tool re-encodes the image. It does not crop it or change its width and height. A 4000×3000 photo is still 4000×3000 after compression; only the file size and the amount of compression artifact change.

When a tiny target cannot be reached without destroying the picture, resize a copy to the dimensions the destination actually displays, then compress that smaller image. Fewer pixels are the reliable way to make a very small file.

4.Choose JPG, WebP, or AVIF for the destination

• JPG is the safest handoff for email, older apps, and forms that only accept JPEG. It does not keep a transparent background.
• WebP is a strong default for websites that already serve modern formats, and it can keep transparency.
• AVIF can produce a smaller file at similar visual quality, but encoding takes longer. Test one representative image before running a large batch.
• Start with 200 KB for a typical web photo, 500 KB when fine detail matters, and 100 KB only for thumbnails or strict upload forms.

5.Read the result before you discard the original

The target is a ceiling, not a promise of an exact byte count. The saved file can be smaller than the number you entered. A highly detailed image can also remain above a very small target at the lowest quality PixelShift will encode.

Check the savings line on the batch, open the result, and keep the original if you may need a cleaner version later. Re-encoding an already compressed file again will not recover detail that the first pass removed.