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PixelFit

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Compress an image to between 20 KB and 100 KB

For a 20–100 KB requirement, aim for 20,480 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 321 × 240 up to 717 × 537 pixels.

20–100 KB

JPG · 20-100 KB (20,480-100,000 bytes) · original pixel size · white background

PixelFit aims between 20,480 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.

Pick a photo to fit it to 20-100 KB (20,480-100,000 bytes).

The result appears here: the exact byte count, pixel size and quality, the size before and after, a preview and a download button.

The safe byte window for 20–100 KB

"At least 20 KB" is 20,000 or 20,480 bytes, so the safe minimum is 20,480. "At most 100 KB" is 100,000 or 102,400 bytes, so the safe maximum is 100,000. The window is 79,520 bytes wide, 80 % of the maximum: wide enough that, at quality 75, the largest 4:3 photo inside it has 5.0 times the pixels of the smallest.

If the best result under 100,000 bytes is below 20,480, PixelFit raises quality, then pads the file only if you opt in (below).

Pixel sizes that land between 20 KB and 100 KB

At quality 75, each kind of image lands in the 20–100 KB window from the first size up to the second.

ImageReaches 20 KB atStays under 100 KB up to
Head-and-shoulders portrait 309 × 385 883 × 1,102
Outdoor landscape (12 MP phone photo) 321 × 240 717 × 537
Scanned typed document page 304 × 382 720 × 904
Handwritten letter with signature 539 × 443 1,358 × 1,116
Flat-colour graphic (flag) 785 × 549 2,689 × 1,882

Open the resizer with a 20–100 KB target →

Fixed pixel sizes against 20–100 KB

When the form fixes the pixels, the file lands in the 20,480–100,000 byte window between these two JPEG qualities; "pad" means even quality 95 stays under 20 KB.

Pixel sizeLowest quality reaching 20 KBHighest quality under 100 KB
140 × 60 (small signature box) none: pad 17,698 bytes 95+
300 × 120 (signature strip) none: pad 10,149 bytes 95+
200 × 230 (small ID photo) 94 95+
413 × 531 (35 × 45 mm at 300 DPI) 45 95+
600 × 600 (2 × 2 inch at 300 DPI) any (30 reaches it) 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 20 KB

Even at quality 95, the highest quality we measured (the tool also tries 100), a 4:3 photo stays under 20,480 bytes up to about 212 × 159 pixels (9 % of the pixels that still fit under 100 KB at quality 75); a handwritten page up to 305 × 250 and a portrait up to 181 × 226. From there to 321 × 240 a photo reaches 20 KB only above quality 75, and from 321 × 240 to 717 × 537 quality 75 lands inside 20–100 KB.

A 300 × 120 image (signature strip) is about 10.1 KB at quality 95, so 50 % of a 20,480-byte file would be padding; a 140 × 60 image (small signature box) is about 2.7 KB at quality 95, so 86 % of a 20,480-byte file would be padding. Padding satisfies a file-size check of 20–100 KB and leaves the pixels unchanged; where the form does not fix the pixel size, a larger image is the cleaner way to reach 20 KB.

Upload sizes against 20–100 KB at quality 75

413 × 531 (about 31.2 KB), 600 × 600 (about 45.5 KB) land inside 20–100 KB as is. Below 20 KB: 300 × 120 (3.8 KB), which needs padding; 200 × 230 (10.2 KB), which reaches it from quality 94. 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 20–100 KB at quality 75, a handwritten page runs from 539 × 443 to 1,358 × 1,116 pixels and a portrait from 309 × 385 to 883 × 1,102.

How to compress an image to 20–100 KB

  1. Open the tool above

    Preset: minimum 20 KB, maximum 100 KB, JPG.

  2. Add the image

    Drop, paste or pick it; the 20,480–100,000 byte window is applied for you.

  3. Fix pixels only if required

    With pixels fixed, only quality moves (and padding, if you allow it, to reach 20 KB).

  4. Download

    name-100kb.jpg; compare its byte count with 20–100 KB.

Sources

  1. Measured by PixelFit with sharp 0.35.5 / libvips 8.18.7 on 31 October 2026.
  2. 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).
  3. 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 20 KB and 100 KB?

Use the tool on this page, preset to 20–100 KB: it returns a JPG of 20,480 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 20 KB?

PixelFit raises the quality first, up to 100. A 300 × 120 image (signature strip) is still only about 10.1 KB at quality 95, 10,149 bytes short of 20–100 KB, so it needs padding: opt in, and a JPEG comment segment adds the missing bytes without touching the picture.

Is a 58.8 KB file inside 20–100 KB?

Yes: anything from 20,480 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 20 KB and 100 KB?

At quality 75: a photo from about 321 × 240 to 717 × 537, a portrait from 309 × 385 to 883 × 1,102.

Related

Ranges sharing a limit

Pixel sizes under 100 KB

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