How to reduce an image to a specific size
- Add your image (or several) using the box above.
- Choose a preset size, or type your own number in the Custom box — for example 75 for 75KB.
- Click Compress. Each file is resized and recompressed until it fits.
- Check the result: it shows the final size, the pixel dimensions and a tick when it's under your limit.
We tested it: one photo, seven sizes
We took one 4.16 MB, 12-megapixel photo from a Pixel 2 and reduced it to different sizes on this page:
| Target | Result | Dimensions | Saved |
|---|---|---|---|
| 10 KB | 9.9 KB | 196×261 | 99.8% |
| 20 KB | 19.9 KB | 277×370 | 99.5% |
| 50 KB | 48.7 KB | 438×584 | 98.9% |
| 100 KB | 96.8 KB | 620×826 | 97.7% |
| 200 KB | 196 KB | 876×1168 | 95.4% |
| 500 KB | 498 KB | 1386×1848 | 88.3% |
| 800 KB | 776 KB | 1753×2337 | 81.8% |
The pattern is simple: to halve the file size you lose roughly 30% of the width and height. Photos from an iPhone 6 Plus and a Galaxy S7 Edge landed on the same dimensions at every size, so this table works as a guide for most phone photos.
Each one took between a quarter of a second and two seconds.
KB, MB and what websites mean
1MB is 1,024KB. So a "2MB limit" is about 2,048KB and a "0.5MB limit" is about 512KB — type those numbers in if a form gives the limit in MB.
Some websites count 1KB as 1,000 bytes instead of 1,024. If an upload is rejected even though the size looks right, set a target a few KB lower.
What happens behind the scenes
The tool first estimates how many pixels your size budget can hold at good quality, resizes to that, then fine-tunes the JPG quality to land just under your limit. If there's still room to spare, it scales back up to use it. The result is the sharpest image that fits — not just the first one that does.
Frequently asked questions
What's the smallest size I can choose?
Any size works, but below about 10KB photos become very small in pixels. If the tool can't reach your target it tells you and gives you the smallest version possible.
Can I reduce image size in KB on my phone?
Yes. The tool runs in mobile browsers, and the compressed image downloads straight to your phone.
Does it change the image's width and height?
Usually yes, because reducing dimensions is the best way to save space while keeping the image sharp. The final dimensions are shown with each result.