Compress image to 100 KB
Reduce an image to exactly 100 KB right in your browser. Perfect for forms, government portals, job applications and email that cap the file size.
The 100 KB target is already set: just upload a photo and the tool finds the quality needed to hit the limit. Processing is local — no upload to a server, no watermark and no signup; batch and JPG/PNG/WebP are supported.
Need exactly 100 KB? Open the compressor (100 KB) →What 100 KB leaves of a photo — our measurement
On September 23, 2026 we ran 20 ordinary photos — people, food, streets, close-ups of texture; 3 to 30 megapixels, 1.1 to 8.9 MB — through this compressor with the target set to 100 KB. All 20 came out under the limit.
| Result | |
|---|---|
| Long side, pixels (smallest / median / largest) | 854 / 1303 / 2400 |
| Megapixels, median | 1.03 |
| JPEG quality chosen | 0.60–0.72 |
| Time per photo, median | 0.9 s |
A 12-megapixel phone frame (4032×3024, 2.4 MB) became 1008×756 at quality 0.70 — 99 KB.
About 1303 pixels on the long side fills most of a laptop screen's width.
Why the picture gets smaller, not blurrier
A size limit can be met two ways: keep every pixel and lower the JPEG quality, or keep the quality and use fewer pixels. The first gives blocks and color blotches; the second gives a smaller but clean picture. Until this measurement the compressor did the first: at 100 KB it kept the full resolution at a median quality of 0.08, and 20 of the 20 photos came out below 0.3. It now looks for the largest size that fits at quality 0.6 or higher and goes lower only for a picture so detailed that nothing else fits. If you need every pixel, untick "Reduce resolution if needed to reach the target size": the tool will then lower only the quality.
The tool counts 1 KB as 1,024 bytes, as Windows does. Some upload forms count 1,000; if a form rejects a file right at the limit, set the target a few KB lower.
Photos: Wikimedia Commons, category "Quality images". They are not republished here — only the numbers.
How to compress an image to 100 KB
- Upload your image (or up to 20 at once).
- Target-size mode and the 100 KB value are already selected.
- Click Compress — the tool tunes the quality — and download the result.
Frequently Asked Questions
How do I compress a photo to exactly 100 KB?
Upload your image — Target-size mode is already set to 100 KB — and click Compress. The tool automatically tunes the quality to stay within 100 KB.
Are my files uploaded to a server?
No. Compression happens entirely in your browser; your files never leave your device.
What if 100 KB can't be reached without heavy quality loss?
For very small targets the tool will, if needed, also reduce the resolution to reach 100 KB, and it tells you when it does.
Is it free and watermark-free?
Yes — free, no signup and no watermark. You can process up to 20 files and download a ZIP.