Reduce image size in KB
Type the size your form asks for. We find the best quality under it.
100% Browser-Based — Files Never Leave Your Device
About Reduce Image Size in KB
Enter any limit, like 30 KB for a signature or 200 KB for a photo, and the tool searches image quality (and, only if needed, pixel size) until the file is strictly under it. It runs in a background Web Worker, so even large phone photos won’t freeze the page, and you can compress a whole batch at once.
How to reduce Image Size in KB
- Select one or more images.
- Enter the maximum size in KB or MB, or tap a preset.
- Click “Reduce image size” and download the result.
Frequently asked questions
Is it safe to reduce my photos here? Are my files uploaded?
Nothing is uploaded. PDFToolsFast runs entirely in your browser using JavaScript and Web Workers, so your files stay on your device. You can even disconnect from the internet after the page loads and the tool keeps working.
What sizes can I choose?
Any size from 5 KB upwards, in KB or MB. Presets cover the most common form limits: 20, 50, 100 and 200 KB.
Will the result be exactly the size I enter?
Just under it, at the highest quality that fits. We aim below N × 1000 bytes so it passes both KB definitions portals use.
Can I keep the exact pixel dimensions?
Yes. Tick “Keep original dimensions” and only JPEG quality changes. If the target is then impossible, you’ll be told the smallest size reached.
Does it support PNG, WebP and iPhone photos?
JPG, PNG, WebP, AVIF, GIF and BMP work in every modern browser. iPhone HEIC photos work in Safari; on other browsers, export as JPG first.