What the size limit actually does
Phone photos are huge: a single 12-megapixel document photo is often 2–4 MB. When you set a limit, PixKB rebuilds the whole PDF at decreasing resolutions and JPEG qualities, measures each real result, and keeps the sharpest version that fits. It's a search, not a guess, so the file lands just under your number.
Here is what that looked like in our own test: three phone photos of printed documents (3024 × 4032 each) plus one iPhone HEIC photo, 13.8 MB in total, combined into a 4-page A4 PDF. Sizes are in decimal units (1 KB = 1,000 bytes), as the tool shows them.
| Limit | PDF size | Page images kept at |
|---|---|---|
| No limit | 2.63 MB | 2480 px (A4 at 300 DPI) |
| 2 MB | 1.70 MB | 2136 px |
| 1 MB | 902 KB | 1707 px |
| 500 KB | 463 KB | 1175 px |
| 200 KB | 186 KB | 751 px |
Each build took about 1–5 seconds in desktop Chromium on our test server. Limits are checked strictly (1 KB = 1,000 bytes), so the file passes portals that count either way. Phones take longer with many pages. At 200 KB for four pages, normal-sized printed text was still readable, but small print starts to blur. If a portal allows it, give each page at least 100 KB of budget.
Document mode for scans
Photos of paper documents carry a lot of useless data: grey-beige paper tone, shadows and camera noise. Document mode converts pages to black and white and pushes the paper to clean white while keeping the ink dark. In our test it made the three document pages about 20% smaller (1.98 MB → 1.60 MB with no limit) and noticeably crisper. Don't use it for photographs of people: it is designed for text.
Page size, orientation and margins
A4 is the safe choice for almost every form and portal outside North America; choose US Letter for US and Canadian systems that ask for it. Auto orientation turns a page landscape only when the image is wider than tall, so a sideways receipt doesn't shrink into a strip. If a photo is sideways, rotate it with ⟳ before building. Fit to each image skips paper sizes altogether and gives every page the image's own shape, which is good for screenshots.
Getting the order right
Portals often expect a specific order: for example, the application form first, then ID, then certificates. The list shows the final page order. Move pages with ↑ ↓ (or drag them on a computer), and remove extras with ✕. Pages are numbered exactly as they will appear in the PDF.
If the PDF is still too big
If you see "still over" after building, the limit is too small for that many pages to stay readable. Try, in order: Document mode, removing pages the portal didn't ask for, splitting the upload if the portal allows several files, or asking whether the limit is per file. Shrinking further would make text unreadable, and a rejected, unreadable scan is worse than an oversized one.
Frequently asked questions
How do I combine multiple JPGs into one PDF?
Choose all the images at once (or add more later with “+ Add more”), arrange them in the list, and press Create PDF. Each image becomes one page, in list order.
Can I make the PDF smaller than 200 KB or 1 MB?
Yes. Type the limit (or tap a chip like 200 KB or 1 MB) before building. The tool tries progressively smaller settings and keeps the sharpest result that fits under your number.
Does it work with iPhone HEIC photos?
Yes. HEIC photos are decoded inside your browser, so there's no need to convert them first.
Are my documents uploaded?
No. The PDF is assembled in your browser's memory and saved straight to your device. You can verify it with your browser's network tab or by turning on airplane mode.
Is there a watermark or page limit?
No watermark. Up to 100 images per PDF; very large batches may be slow on older phones.