Big photos under 1 MB
The 12 MP test photo, 4000 x 2667 pixels and 1.81 MB as a high quality JPEG, came down to 992 KB at quality 82 without losing a pixel. That is the usual case for a phone photo: 1 MB is enough to keep the full resolution with a quality setting you will not notice.
The smaller 2000 x 1333 photo was already 694 KB, under the limit, so it was left as it was.
| Test image | Original | Result | JPEG quality | Pixels | Time |
|---|---|---|---|---|---|
| Photo | 694 KB | 694 KB | Kept as is | 2000 x 1333 | 4 ms |
| 12 MP photo | 1.81 MB | 992 KB | 82 | 4000 x 2667 | 15.5 s |
| Screenshot | 46 KB | 115 KB | 95 | 1600 x 900 | 417 ms |
| Illustration | 94 KB | 81 KB | 95 | 1200 x 1200 | 432 ms |
Test images are synthetic files made by this project: a 2000 x 1333 landscape photo, a 1600 x 900 interface screenshot and a 1200 x 1200 transparent illustration. The 12 MP photo is the same photo scaled up to 4000 x 2667, the size a phone camera saves. Quality is lowered first and the image is only scaled down when quality alone cannot reach the target. A JPEG that is already under the target is left as it is. Timings: one thread of WebAssembly on Node v22.23.4, Intel(R) Xeon(R) Processor @ 2.10GHz, 2 cores, measured 2026-10-31. Other devices will differ.
Files under the limit stay untouched
A JPEG that already fits is not compressed again. Only its metadata is removed. Compressing a JPEG twice adds loss each time, so leaving it alone keeps the best possible picture.
A PNG is converted to JPEG unless you choose Same under Save as. The screenshot in the table became a 115 KB JPEG.
Where a 1 MB limit comes up
- Email services and chat apps that limit attachments.
- Government and university portals that accept photos and scans up to 1 MB.
- Marketplaces and listing sites with a per-photo cap.
- Website builders and content systems that refuse large uploads.
PNG and screenshots over 1 MB
A large PNG screenshot can only get under 1 MB as a PNG by losing pixels, since PNG compression has no quality setting. Saving it as JPEG or WebP usually brings it well under the limit at full size. WebP keeps text cleaner than JPEG at the same size.
Many photos at once
Drop a set of photos and each one is brought under 1 MB. Up to five start on their own; for more, press the button in the bar at the bottom. Download them one by one or as a ZIP. The free limit is 10 images a day.
Questions
Will my photo lose resolution?
Rarely. Most phone photos fit under 1 MB at full size. The result card says if the pixels were scaled.
Why was my file not changed?
It was already a JPEG under 1 MB, so it was left as it was apart from removing metadata.
Does 1 MB mean 1000 KB or 1024 KB?
Here it means 1,000,000 bytes. A file under that also passes a limit counted in 1024-byte units.