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JPG to PDF under 100 KB

To make a PDF under 100 KB, PixelFit compresses the JPG to at most 99,262 bytes and wraps it in a one-page PDF with about 738 bytes of PDF structure, 100,000 bytes or less in total. Measured: an A4 scan fits up to 104 DPI at quality 50; a 4:3 photo at about 715 × 536 pixels (quality 75).

PDF under 100 KB

PDF · under 100 KB (at most 100,000 bytes) · original pixel size · white background

PixelFit aims at 100,000 bytes or less, so the file passes whether the form counts 1 KB as 1,000 or 1,024 bytes.

Fit, background and padding white background · page the size of the picture

Saving presets is part of Pro.

Pick a photo to fit it to under 100 KB (at most 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.

Where the 100 KB go in a JPG-to-PDF file

Of the 100,000 bytes that pass as 100 KB under both KB definitions, PDF structure takes 738 bytes for one A4 page (computed with PixelFit's own writer), leaving 99,262 bytes, 99.2 %, for the JPEG; ten pages leave 9,475 bytes each.

For one photo, quality 75 allows 715 × 536 pixels and quality 90 559 × 419; a full 12 MP frame must be scaled down first, which the tool does for you.

How many pages fit in a 100 KB PDF

The 100,000 bytes of 100 KB, less 738 bytes of PDF structure for the first page and about 501 for each extra one, shared evenly.

PagesJPEG bytes per pageMax A4 DPI at q50Max A4 DPI at q75A4 at 150 DPI
1 page 99,262 104 DPI 81 DPI no: 1.3× over at q30
2 pages 49,383 69 DPI 54 DPI no: 2.5× over at q30
3 pages 32,755 55 DPI 44 DPI no: 3.8× over at q30
5 pages 19,452 41 DPI 33 DPI no: 6.4× over at q30
10 pages 9,475 29 DPI 23 DPI no: 13.2× over at q30
20 pages 4,487 19 DPI 15 DPI no: 27.9× over at q30

Make a PDF under 100 KB →

Phone photos in one PDF under 100 KB

Largest 4:3 photo per page, in pixels, when 1 to 10 photos share 100,000 bytes; "full" means a 12 MP phone photo keeps all its pixels (the tool never enlarges).

PhotosQuality 60Quality 75Quality 90
1 photo 827 × 620 715 × 536 559 × 419
2 photos 583 × 437 506 × 379 394 × 295
3 photos 477 × 357 411 × 308 317 × 237
5 photos 365 × 273 312 × 234 241 × 180
10 photos 249 × 186 215 × 161 163 × 122

A4 and Letter pixel sizes against 100 KB

One typed page per DPI: its pixels, the quality it gets alone in 100 KB, and how many fit at quality 75.

DPIA4 pixelsOne A4 page under 100 KBLetter pagePages at q75
72 DPI 595 × 842 quality 82 quality 83 1
100 DPI 827 × 1169 quality 55 quality 58 none
150 DPI 1240 × 1754 no: 1.3× over at q30 no: 1.2× over at q30 none
200 DPI 1654 × 2339 no: 1.9× over at q30 no: 1.9× over at q30 none
300 DPI 2480 × 3508 no: 3.4× over at q30 no: 3.3× over at q30 none

Readable pages and photos in 100 KB

100 KB fits one typed A4 page scanned at up to 104 DPI at quality 50 (our readability threshold); a 300 DPI scan gets nothing: even quality 30 is 3.4 times too big. Scan at 100 DPI or crop to the text.

What fits at a readable 150 DPI is a crop: a full-width strip about 145 mm high (49 % of the page, roughly 28 lines of 12-point type at single spacing) at quality 50. For a certificate or mark sheet, crop to the part the form needs before you convert.

Under 100 KB a full 150 DPI A4 scan gets nothing: even quality 30 is 1.3 times too big, and no photo of 1600 × 1200 fits at quality 70.

One image free, several merged with Pro

Free: each image becomes its own one-page PDF under 100 KB. Pro: several images merged into one PDF under 100 KB, on your device; 2 pages get 49,383 bytes of JPEG each.

How to turn a JPG into a PDF under 100 KB

  1. Open the tool above

    Preset: PDF output, at most 100 KB.

  2. Add the JPG

    Drop, paste or pick it (PNG, WebP and HEIC work too).

  3. Choose the page

    Keep the picture's own size or fit it on A4 or Letter.

  4. Download

    name-100kb.pdf arrives with its exact byte count (100,000 bytes or less).

Forms with a 100 KB PDF limit

Upload specs in our dataset with a PDF limit of exactly 100 KB. Verify with the official notice before you submit.

100 KB PDF uploads

Sources

  1. Measured by PixelFit with sharp 0.35.5 / libvips 8.18.7 on 31 October 2026.
  2. Samples, Wikimedia Commons, checked 31 October 2026: typed page (public domain) commons.wikimedia.org/w/index.php?curid=194775753; landscape (CC0 1.0) commons.wikimedia.org/w/index.php?curid=154070378
  3. Paper sizes, Markus Kuhn, checked 31 October 2026: cl.cam.ac.uk/~mgk25/iso-paper.html
  4. PDF format, Library of Congress, checked 31 October 2026: loc.gov/preservation/digital/formats/fdd/fdd000474.shtml

Frequently asked questions

How do I convert a JPG to PDF under 100 KB?

Drop the JPG into the tool on this page, preset to PDF under 100 KB: the picture is compressed to 99,262 bytes or less, so the PDF ends at or below 100,000 bytes.

Can I convert JPG to PDF for free?

Yes, one image per PDF, with no upload. Under 100 KB a 4:3 photo keeps 715 × 536 pixels at quality 75; merging several JPGs is Pro.

How many pages fit in a 100 KB PDF?

Under 100 KB, not even one full A4 page at 150 DPI keeps quality 50; one page fits at 100 DPI.

What DPI should a scan have for a 100 KB PDF?

For one typed A4 page, at most 104 DPI at quality 50, or 81 DPI at quality 75, under 100 KB; of the usual 72 to 300 DPI settings, 100 DPI.

Why is the PDF bigger than my JPG?

A PDF wraps the JPEG in page, image and cross-reference objects: 738 bytes for one page in PixelFit's writer, about 501 more per added page.

Related

Other PDF size limits

More for 100 KB

Pixel sizes that fit 100 KB

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