Reduce Image Size in KB Online Free
Shrink any image to a specific KB size for forms, portals and email — instantly.
or drag & drop your image here
Pick a target size. The tool automatically lowers quality (and dimensions only if needed) until your file fits — no upload, all in your browser.
Why compress images to an exact KB size?
Government forms, job portals, email attachments and websites all set upload limits in KB, and hitting the exact target is what gets your file accepted. This free tool compresses any JPG, PNG or WEBP to the size you pick — from 20KB to 1MB — lowering quality first and only shrinking dimensions when needed.
The tool stops at the highest quality that still fits your target, so your image keeps as much detail as possible. Drop in your file and download the optimized result in seconds.
Because processing happens locally with the HTML5 canvas API, nothing is uploaded and there are no daily limits. Try Compress to 100KB or Resize Image in KB.
How to compress an image to an exact KB size
Upload your image
Click "Choose Image" or drag and drop your JPG, PNG or WEBP file. The file is processed entirely on your device.
Pick your target
Choose the target file size. The tool lowers quality first to keep your dimensions, and only reduces dimensions if the target is very small.
Download the compressed image
When the file fits your target, click Download. Check the before/after sizes to see how much you saved.
Why use the exact-KB compressor?
Fits your target every time
Lowers quality just enough to hit your target, keeping your dimensions when it can.
Private by Design
Images never leave your device — processed 100% in your browser.
100% Free
No signup, no watermarks, no limits. Use it as much as you need.
Instant results
Fast local processing — no waiting queues.
Frequently Asked Questions
How do I reduce an image size in KB?
Upload your image, pick your target size (20KB to 1MB), and FastResize lowers quality — and dimensions if needed — until the file fits. Download when ready.
Why does my image need to be a specific KB size?
Many websites, government portals and application systems reject files above a set limit, like 50KB or 100KB. Reducing the KB size makes the file accepted and loads much faster.
What is the fastest way to reduce KB without visible quality loss?
Start with the largest target that still meets the requirement (e.g. 100KB instead of 50KB) and keep JPG output for photos. That preserves the most visual quality.
Can I reduce the size of a PNG?
Yes. PNGs are lossless and large, so the tool may also shrink the dimensions to hit your target. Converting to JPG usually gives much smaller files.
Is there a file size limit for uploads?
The tool works with images up to about 50MB. Larger files just take a little longer to process locally.