50 KB: balance pixel dimensions with compression
A 50 KB result can fail for two different reasons: the picture may have too few pixels, or it may have enough pixels but poor detail. Read the width and height before judging the preview. Automatic sizing has no extra dimension cap, but the compressor can still resize to fit its processing and byte budget.
Begin with your original and no extra dimension cap. If your form specifies maximum dimensions, apply the appropriate cap and compare the new result. A low-quality enlarged image will not become sharper merely because its file is under 50 KB. Crop unnecessary background before selecting the file when you need more of the available pixels devoted to the subject.
Measured 50 KB examples
Measured with the actual ExactKB compressor in Chrome 155.0.8059.84 on macOS, using decimal units, automatic dimensions and no size preset. Encoder percentages are settings, not measured detail retention. Results vary with the image and browser. Files are synthetic, contain no customer images, and are available below so you can reproduce the comparison.
The textured PNG input is 3,031,966 bytes at 1200×900. Download the textured original.
On a narrow screen, scroll the results table sideways to see all columns.
| Input / target | Output bytes | Output pixels | Encoder setting | Inspect file |
|---|---|---|---|---|
| Texture / 50 decimal KB / JPG | 49,931 | 1033×775 | 61% | Download output |
| Texture / 100 decimal KB / JPG | 95,925 | 1200×900 | 67% | Download output |
To reproduce: upload the matching original above, choose the target shown in the row (this page starts at 50 KB), turn off the 1024-byte option, leave Longest side on Automatic and select the table’s output format. Press Compress and compare exact bytes and dimensions. The decimal ceiling is 50,000 bytes; leaving binary units enabled instead permits 51,200 bytes.
When the 400 px preset is the wrong choice
The Photo 50 preset combines a 50 KB budget with a 400 px longest-side cap. That is a convenience, not an application standard. For a 4:3 input its bounding box is at most 400×300; it cannot satisfy a hypothetical 450×450 minimum. Use the ordinary 50 KB target and the required crop instead. Our automatic textured example retained 1033×775, but that does not promise the same dimensions for a different image.
Before using the download
If the result says “Could not fit”, its download is an above-limit best effort, not a successful compression. Do not upload it as a file that meets your cap. Try a larger permitted budget or prepare a simpler crop from the original.
Open the downloaded result and inspect the detail your task requires. Confirm format, actual bytes and both dimensions against the destination’s current instructions. A successful size badge does not validate composition or a separate minimum file size.
Compare 100 KB · How quality and dimensions are chosen · Troubleshoot a rejected upload