Compress JPEG to 50KB — Free, Fast & Private
A form that says "JPEG, maximum 50 KB" is asking for two things at once: the format and the size. This page fixes the format. The compressor opens on JPEG with the target already at 50 KB, so the only job left is to drop the file in and read the number. What follows is what the tool does to get there, what that costs the picture, and what it tells you when 50 KB is out of reach.
How a JPEG is fitted to 50 KB
JPEG has a continuous quality dial, and that is what makes it the easy format to steer toward a byte count. The tool encodes once at high quality; if that already fits, you keep every pixel and you are done. If not, it encodes once at the lowest quality it will use. If even that misses, it does not spend a long search proving it and goes straight to making the picture smaller. When the answer lies between the two, it interpolates on the logarithm of the size to find the highest quality that still fits, with a fixed number of probes so it always finishes.
Quality is spent before pixels. Only when the lowest quality still misses does the tool reduce the dimensions, in steps, and search quality again at the smaller size. The finished file is measured, and a miss is reported as a miss: you get the smallest file it managed and its real size, never a rounded-down figure.
What fits in 50 KB — measured on this page
We dropped five real files on the compressor above and kept what it handed back. 5 of 5 came out under 50 KB; 3 were made smaller in pixels to get there, because past a point the bytes can only come from pixels.
| File | Before | After, on this page | Under 50 KB? |
|---|---|---|---|
| 12 MP phone photo | 4032 × 3024 px · 3.73 MB | 2016 × 1512 px · 39.4 KB | Yes |
| Portrait / headshot | 3264 × 4653 px · 2.25 MB | 2611 × 3722 px · 46.8 KB | Yes |
| Scanned handwritten page | 3349 × 4281 px · 2.17 MB | 2143 × 2740 px · 46.8 KB | Yes |
| Scanned signature | 2041 × 617 px · 109.1 KB | 2041 × 617 px · 48.6 KB | Yes |
| Screenshot (PNG) | 1280 × 800 px · 88.1 KB | 1280 × 800 px · 48.6 KB | Yes |
Measured 2026-10-06 in Chromium 145.0.7632.6 with this page’s own settings. The photos are public-domain and CC0 files from Wikimedia Commons; the screenshot is our own. Sizes read as the tool shows them (1 KB = 1,024 bytes); the target itself is 50,000 bytes, which is under 50 KB on either reading.
What is different about JPEG at this size
Because the dial is continuous, a JPEG lands close under the ceiling instead of far below it, so a file that has to be under 50 KB usually comes out only a little under it. That is the point: the quality you keep is the highest the limit allows. It is also why a large, detailed photograph can need its dimensions reduced as well, while a scan of a signature or a plain document often fits on quality alone. The table on this page shows the two cases on real files.
If your picture is a PNG or a screenshot and the form wants JPEG, this page converts it: the output is a JPEG, and a PNG with transparency is flattened, because JPEG cannot hold transparency. If the form insists on PNG instead, use the PNG page, which takes a different route to the same limit.
Decimal kilobytes
KB here is 1,000 bytes. A file under that is also under a portal that counts 1,024-byte kilobytes, so the decimal reading is the safe one for either kind of form.