Compress Image to Exact KB
How to use the Compress Image to Exact KB
- Choose a JPG, PNG or WebP image, or drop it onto the box. Its format, dimensions and file size appear straight away.
- Pick a target: 20 KB, 50 KB, 70 KB, 100 KB, 200 KB, 500 KB, 1 MB, or Custom to type any size from 5 KB to 50 MB.
- Keep the output format on Auto to keep the original format, or choose JPG, WebP or PNG. Tick Reduce dimensions if needed only if a smaller width and height are acceptable.
- Select Compress. When the result shows "Under target ✓", the file has been checked to be at or below your target. Download it.
Examples
- A 3.2 MB phone photo for a form that accepts 200 KB: usually fits as a JPG at the original dimensions, at a quality chosen by the search.
- A passport-style photo for a 50 KB limit: often fits as a JPG. If the photo is very large, the tool may ask you to allow smaller dimensions first.
- A transparent PNG logo for a 20 KB limit: PNG can only get smaller by shrinking, so the tool offers WebP, which keeps transparency, before changing anything.
How to compress an image to a specific KB size
Upload forms often set a hard limit, such as 50 KB, 100 KB or 200 KB. Choose that limit as your target, compress the image, and download the file once it shows Under target ✓. Sizes use 1 KB = 1,000 bytes, so a file under 50 KB here is also under a 50 KB limit that counts 1 KB as 1,024 bytes.
Why normal image compressors may not hit a specific file size
Most compressors ask for a quality setting, such as 75%, not a size. The same quality gives very different sizes for different photos: a detailed landscape at 75% might be 900 KB, while a plain screenshot is 80 KB. You end up guessing, compressing again and checking the size by hand.
How CHARTOVANA reaches the target
The tool decodes your image once, then searches for the highest JPG or WebP quality that still fits, using a binary search: it tries the middle quality, then halves the range towards the target each time. It needs about 8 attempts, and every attempt is measured by its real file size, so it never reports an estimate as a result.
PNG is lossless, so quality can’t make it smaller; only smaller dimensions can. If a target can’t be reached, the tool says so and shows the smallest file it made. It suggests your options, such as allowing smaller dimensions or switching to WebP or JPG. Nothing about the size or format changes unless you choose it.
When a result is marked successful, the generated file has been verified to be at or below the selected target size. Very small targets for very large or detailed images may not be reachable at the original dimensions.
Privacy and browser processing
Compression runs in a background worker in your browser. Your image isn’t uploaded or stored anywhere, and the result exists only in your browser’s memory until you download it or leave the page. Compressed files don’t keep the original’s metadata, such as camera details or location. To compress many images at a chosen quality instead, use the Image Compressor. To set exact dimensions, use the Image Resizer.
Frequently asked questions
How do I compress an image to 50 KB, 100 KB or 200 KB?
Choose the image, select 50 KB, 100 KB or 200 KB as the target and select Compress. Download the file when it shows Under target ✓. For any other size, choose Custom and type it in KB or MB.
Is the result guaranteed to be under my target?
When the result is marked Under target ✓, the file has been checked and is at or below the target. Some targets can’t be reached for some images. In that case the tool says Not under target, explains why and offers the smallest result. It never claims success it hasn’t verified.
Will my image be resized?
Not unless you allow it. Reduce dimensions if needed is off by default, so the width and height stay the same. If the target can’t be reached at the original dimensions, the tool tells you and lets you choose.
What happens to transparent images?
PNG and WebP keep transparency. JPG has none, so if you choose JPG, transparent areas are filled with a background colour you pick, white by default. The tool never switches a transparent PNG to JPG on its own.
Why is my file smaller than the target?
The search keeps the highest quality that fits, and the next quality step up would go over. A small gap below the target is normal. If your image is already under the target, the original is kept unchanged.
Is my image uploaded?
No. Everything happens in your browser, and your image never leaves your device. There is no sign-up.
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