Compress Image to 80KB
Need your image under 80KB? This size is typically requested for Certificates, and our compressor hits it precisely without guesswork.
Drop your image here, or browse
[ Supports JPG • JPEG • PNG • WEBP ]
Convert Image to a Specific KB Size
Not sure what size you need? Every preset on the calibrated ruler below is mapped to its primary real-world requirement. Scroll or swipe to locate your target.
◄ SWIPE HORIZONTALLY TO ROTATE MEASURING DIAL • CLICK TO SELECT SPECIFIC TARGET LIMITS ►
About This MB to KB Converter
Also searched as a photo resizer in MB, an image resizer in MB, or simply a kb converter - this tool shrinks your photo from megabytes down to the exact kilobyte size a form, portal, or website actually accepts, and converts the format at the same time if you need that too.
Common Use: Used for certificates requiring images under 80KB.
Convert MB to KB in 3 Steps
Reducing image size is quick and simple. Just follow these steps.
Drop Your Image
JPG, PNG, or WebP. Drop your files into the box at the top, or click browse to choose images.
Set Target Size
Type your target size in KB, or simply tap one of our pre-mapped quick size buttons above.
Download Output
Your file is converted and ready. Preview the size savings and download instantly.
Also Convert the Format
Need a different file type too? Switch the output format in the same step - upload a PNG, download a JPG. No separate image converter needed.
| Format | Pick this when... |
|---|---|
| JPG / JPEG | You need the smallest file - best for photos, signatures, scans, and any mb to kb converter photo job |
| PNG | You need transparency or sharp text/logos |
| WebP | You're optimizing images for a website - smaller than JPG or PNG (see the official Google WebP spec) |
| HEIC / HEIF | Converting iPhone photos so they open on any device or upload form |
| Turning a compressed image into a document, or pulling an image out of a PDF | |
| SVG | Vector graphics, icons, and logos that need to scale without quality loss |
| GIF | Simple animations or images with limited colors |
| BMP | Uncompressed Windows bitmap files, legacy software compatibility |
| TIFF | High-quality scans and print-ready documents |
| PSD | Photoshop files - convert to JPG/PNG for sharing outside Photoshop |
| RAW / DNG | Camera RAW photos - convert to JPG for easy viewing and sharing |
| AVIF | Next-gen web format, even smaller than WebP (defined by the AOMedia AVIF standard) |
| ICO | Website favicons and app icons |
| APNG | Animated PNG - like GIF but with better quality and transparency |
Need to shrink a PDF instead? Try our PDF Compressor.
Resize Images by Pixels
Need to change the actual dimensions, not just the file size? Open Advanced Settings and set a Max Width or Max Height in pixels - useful when a form asks for both a size limit (like 100 KB) and a dimension limit (like 600x800px) together. Leave it blank and we'll only adjust quality to hit your KB target; set a max dimension and we'll resize the image itself before compressing.
This is different from the mb to kb size conversion above: compressing changes file size (KB/MB) by adjusting quality, while resizing changes the actual pixel width and height. Use one, or both together, depending on what your form or website requires.
MB vs KB - Why Your Numbers Don't Match
Uploaded your photo elsewhere and got a different KB number than expected? Here's why: 1 MB usually equals 1024 KB (the standard your phone and computer use), but some websites calculate it as 1000 KB instead. That's not a bug - it's just two different counting systems (refer to the standard kilobyte binary conventions). If you need to compress it to a specific size, we recommend matching your exact target requirement.
Either way, don't guess - check the live size shown after compression here before you download, so you know exactly what you're uploading.
Searching for a kb to mb converter instead - trying to go the other way? The math works the same in reverse: divide your KB number by 1024 to get MB. Most people asking this are really just trying to check whether their file fits a size limit, which is exactly what the live preview here confirms before you download - no separate kb to mb calculation needed.
3 Mistakes That Ruin a Compressed Photo
Avoid these common slip-ups to ensure your uploaded images are approved.
Compressing too aggressively
Going straight to 20 KB for signatures when the form allows 100 KB throws away quality you didn't need to lose.
Uploading the wrong format
PNG files compress worse than JPG for photos - if your PNG won't hit the target size, switch to JPG first.
Not checking the preview
Always glance at the compressed result before downloading - some forms reject images that look too soft or pixelated, even if the KB size is correct.
Built Different: Everything Happens On Your Device
Most image converters upload your file to a server, compress it there, then send it back. We don't. Your photo is processed entirely inside your browser - nothing is ever transmitted, stored, or seen by anyone. That matters if you're compressing ID cards, signatures, or personal documents, not just casual photos.
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"This is a lifesaver! I had to compress my university admissions documents down to exactly 150 KB. The PDF Compressor met the target instantly without losing any readability."
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