How to reduce image size in KB
- Tap Choose image or drag a photo into the box.
- Type your maximum size, for example 50 KB, or tap a quick pick.
- Tap Compress image and check the result in the yellow tag.
- Tap Download image.
Sizes people use most
| Upload type | Typical limit | Shortcut |
|---|---|---|
| Signature for online forms | 10–20 KB | 20 KB tool |
| Exam and recruitment photos | 20–50 KB | 50 KB tool |
| Job portals and university forms | 100 KB | 100 KB tool |
| Visa and ID applications | 200–240 KB | 200 KB tool |
| Email and website uploads | 500 KB–1 MB | 500 KB tool |
Limits vary by form and change over time, so always check the instructions on the portal you're using.
Why portals ask for a size in KB
Government, exam and job portals store millions of uploads, so they cap each file to keep storage and page loads small. The limit is usually written like "JPG, 20–50 KB" or "maximum 100 KB". A modern phone photo is 2–5 MB, which is 40 to 250 times larger than most limits.
File size depends on two things: the pixel dimensions and the compression quality. ResizeKB first lowers JPG quality in small steps until the file fits, because that keeps the full picture sharp. Only when quality alone can't reach your target does it also reduce the width and height, and it tells you when that happens.
What if the portal has a minimum size too?
Some forms say "between 20 KB and 50 KB". Set the target to the maximum (50 KB). The result usually lands just below it, well above the minimum. If a tiny image comes out under the minimum, use the image resizer to make it larger first, then compress again.
Is it safe to upload my photo?
Your image is never uploaded. ResizeKB processes files inside your own browser using the same technology that draws images on web pages, so the photo never leaves your phone or computer. That matters for documents like passport photos, ID scans and signatures. You can even disconnect from the internet after the page loads and the tool keeps working.
Frequently asked questions
How do I reduce a photo from MB to KB?
Choose the photo, enter the KB limit (for example 100) and tap Compress image. A 4 MB phone photo typically becomes 100 KB in a second or two, with the same width and height.
Which format gives the smallest file?
JPG is the best choice for photos and is accepted almost everywhere. WebP can be smaller still, but many government portals don't accept it yet.
Why does the tool sometimes change my image dimensions?
If even the lowest sensible quality is still above your limit, the only way to go smaller is fewer pixels. The tool reduces width and height just enough and tells you the new size.
Do you keep a copy of my image?
No. The image is processed in your browser and is never sent to our server.
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Last updated 2026-10-27