FreeImageToolkitCompress Image to an Exact Size in KB
Need a photo under a specific size for an online form, job portal or email? Set the target in KB and this tool automatically finds the best quality that fits. No guessing with quality sliders.
How to Compress an Image to your target size
- Drop one or more photos into the upload area above (JPG, PNG, WebP, GIF or BMP).
- The target is already set to your target size. Change it with the presets or type your own number.
- The tool finds the highest quality that fits. If the photo is still too large, it reduces the pixel dimensions slightly.
- Check the final size and dimensions in the list, then click Download. Several files are saved as one ZIP.
Popular Target Sizes
| Target size | Typical result for a photo | Common use |
|---|---|---|
| 20 KB | about 300–500 px wide | Signatures, small ID photos in exam forms |
| 50 KB | about 500–800 px wide | Application photos, profile pictures |
| 100 KB | about 800–1200 px wide | Online forms, email, listings |
| 200 KB | about 1200–1800 px wide | Websites, marketplaces, documents |
Why Not Just Lower the Quality?
Quality settings do not map to file size: the same 70% can give 40 KB for one photo and 400 KB for another. This tool works backwards from the size you need. It tests quality levels until the file fits, then keeps the highest one. If a large photo cannot fit even at reasonable quality, it scales the image down a little. That looks much better than over-compressing a huge image.
Results are saved as JPG by default, the format almost every form accepts. Transparent areas become white. If you only need a smaller file without a size limit, use the regular image compressor.
Frequently Asked Questions
How do I reduce an image to a specific size in KB?
Upload the image, enter the size you need (for example 50) and download. The tool picks the best quality and, if needed, slightly smaller dimensions so the file stays under that size.
Is 1 KB 1,000 or 1,024 bytes?
We treat 1 KB as 1,000 bytes, so a 50 KB result is at most 50,000 bytes. That keeps the file under the limit whether the website counts 1 KB as 1,000 or 1,024 bytes.
Will my photo lose quality?
Some detail is always lost when a file gets much smaller. The tool keeps the highest quality that fits and prefers slightly reducing dimensions over heavy compression artifacts.
Can I compress PNG to a size in KB?
Yes. PNG, WebP, GIF and BMP files are converted to JPG, which reaches small sizes far more easily. Transparent backgrounds become white.
Are my photos uploaded?
Yes. Everything runs in your browser. Your photos are never uploaded, which matters for ID photos, signatures and documents.