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Compress an image to between 50 KB and 100 KB
For a 50–100 KB requirement, aim for 51,200 to 100,000 bytes: that window passes whether the form counts 1 KB as 1000 or 1024 bytes. At quality 75 a 4:3 photo lands inside it from about 515 × 386 up to 717 × 537 pixels.
50–100 KB
JPG · 50-100 KB (51,200-100,000 bytes) · original pixel size · white background
PixelFit aims between 51,200 and 100,000 bytes, so the file passes whether the form counts 1 KB as 1,000 or 1,024 bytes.
Fit, background and padding white background · padding off
Saving presets is part of Pro.
The result appears here: the exact byte count, pixel size and quality, the size before and after, a preview and a download button.
The batch kit (one ZIP for up to 500 photos, several photos merged into one PDF) is part of Pro.
The safe byte window for 50–100 KB
"At least 50 KB" is 50,000 or 51,200 bytes, so the safe minimum is 51,200. "At most 100 KB" is 100,000 or 102,400 bytes, so the safe maximum is 100,000. The window is 48,800 bytes wide, 49 % of the maximum: narrow enough that a fixed pixel size has only a short band of qualities landing inside.
If the best result under 100,000 bytes is below 51,200, PixelFit raises quality, then pads the file only if you opt in (below).
Pixel sizes that land between 50 KB and 100 KB
At quality 75, each kind of image lands in the 50–100 KB window from the first size up to the second.
| Image | Reaches 50 KB at | Stays under 100 KB up to |
|---|---|---|
| Head-and-shoulders portrait | 571 × 713 | 883 × 1,102 |
| Outdoor landscape (12 MP phone photo) | 515 × 386 | 717 × 537 |
| Scanned typed document page | 492 × 618 | 720 × 904 |
| Handwritten letter with signature | 918 × 754 | 1,358 × 1,116 |
| Flat-colour graphic (flag) | 1,629 × 1,140 | 2,689 × 1,882 |
Fixed pixel sizes against 50–100 KB
When the form fixes the pixels, the file lands in the 51,200–100,000 byte window between these two JPEG qualities; "pad" means even quality 95 stays under 50 KB.
| Pixel size | Lowest quality reaching 50 KB | Highest quality under 100 KB |
|---|---|---|
| 140 × 60 (small signature box) | none: pad 48,418 bytes | 95+ |
| 300 × 120 (signature strip) | none: pad 40,869 bytes | 95+ |
| 200 × 230 (small ID photo) | none: pad 28,777 bytes | 95+ |
| 413 × 531 (35 × 45 mm at 300 DPI) | 90 | 95+ |
| 600 × 600 (2 × 2 inch at 300 DPI) | 79 | 93 |
| 800 × 600 (4:3 web photo) | any (30 reaches it) | 63 |
| 1200 × 1600 (3:4 portrait upload) | any (30 reaches it) | 44 |
What falls below 50 KB
Even at quality 95, the highest quality we measured (the tool also tries 100), a 4:3 photo stays under 51,200 bytes up to about 342 × 256 pixels (23 % of the pixels that still fit under 100 KB at quality 75); a handwritten page up to 500 × 411 and a portrait up to 332 × 414. From there to 515 × 386 a photo reaches 50 KB only above quality 75, and from 515 × 386 to 717 × 537 quality 75 lands inside 50–100 KB.
A 200 × 230 image (small ID photo) is about 21.9 KB at quality 95, so 56 % of a 51,200-byte file would be padding; a 140 × 60 image (small signature box) is about 2.7 KB at quality 95, so 95 % of a 51,200-byte file would be padding. Padding satisfies a file-size check of 50–100 KB and leaves the pixels unchanged; where the form does not fix the pixel size, a larger image is the cleaner way to reach 50 KB.
Upload sizes against 50–100 KB at quality 75
No size we track lands inside 50–100 KB as is. Below 50 KB: 413 × 531 (31.2 KB), which reaches it from quality 90; 600 × 600 (45.5 KB), which reaches it from quality 79. Just above 100 KB: 800 × 600 (about 124,200 bytes), 1080 × 1080 (about 307,000 bytes), which need a lower quality or fewer pixels.
Inside 50–100 KB at quality 75, a handwritten page runs from 918 × 754 to 1,358 × 1,116 pixels and a portrait from 571 × 713 to 883 × 1,102.
How to compress an image to 50–100 KB
-
Open the tool above
Preset: minimum 50 KB, maximum 100 KB, JPG.
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Add the image
Drop, paste or pick it; the 51,200–100,000 byte window is applied for you.
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Fix pixels only if required
With pixels fixed, only quality moves (and padding, if you allow it, to reach 50 KB).
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Download
name-100kb.jpg; compare its byte count with 50–100 KB.
Forms that ask for 50–100 KB
Upload specs in our dataset with exactly this window. Verify with the official notice before you submit.
Sources
- Measured by PixelFit with sharp 0.35.5 / libvips 8.18.7 on 31 October 2026.
- Sample images, Wikimedia Commons, checked 31 October 2026: landscape (CC0 1.0) commons.wikimedia.org/w/index.php?curid=154070378; portrait commons.wikimedia.org/w/index.php?curid=23956389; typed page commons.wikimedia.org/w/index.php?curid=194775753; handwritten letter commons.wikimedia.org/w/index.php?curid=90423615; flag commons.wikimedia.org/w/index.php?curid=361734 (public domain).
- Binary prefixes, NIST, checked 31 October 2026: physics.nist.gov/cuu/Units/binary.html
Frequently asked questions
How do I compress an image to between 50 KB and 100 KB?
Use the tool on this page, preset to 50–100 KB: it returns a JPG of 51,200 to 100,000 bytes. A 4:3 photo stays under 100 KB up to about 717 × 537 at quality 75.
What if my image comes out smaller than 50 KB?
PixelFit raises the quality first, up to 100. A 200 × 230 image (small ID photo) is still only about 21.9 KB at quality 95, 28,777 bytes short of 50–100 KB, so it needs padding: opt in, and a JPEG comment segment adds the missing bytes without touching the picture.
Is a 73.8 KB file inside 50–100 KB?
Yes: anything from 51,200 to 100,000 bytes passes under both KB definitions. Exactly 102,400 bytes passes only where 1 KB = 1024 bytes.
Which pixel size lands between 50 KB and 100 KB?
At quality 75: a photo from about 515 × 386 to 717 × 537, a portrait from 571 × 713 to 883 × 1,102.
Related
Single limits
- Compress to 45 KB
- Compress to 50 KB Maximum only
- Compress to 60 KB
- Compress to 90 KB
- Compress to 100 KB Maximum only
- Compress to 120 KB
Ranges sharing a limit
Pixel sizes under 100 KB
- 800×480 (WVGA) about 97.1 KB as a quality-75 JPG
- 51×51 mm photo about 91.6 KB as a quality-75 JPG
- 2×2 inch photo about 91 KB as a quality-75 JPG