PNG to PDF
In your browser, no upload
a page per image · no quality lost
Specification
6 rows| Item | Value | Notes |
|---|---|---|
| Input | JPG, PNG, HEIC, WebP, AVIF, GIF, BMP, TIFF | Read from the file itself, not its name |
| Output | One PDF | A page per image, in the order you pick them |
| Transparency | Kept | As a soft mask, the way PDF stores alpha |
| Pixels | Every one the same | Copied as stored, or unpacked and stored without loss |
| Page size | Image size, A4 or Letter | The page scales the image; its pixels are not resampled |
| Processed in | This browser | Not sent to a server |
What happens
4What happens, and why
Drop one or more PNGs — screenshots, scans, diagrams — and they become one PDF, a page each, in the order you picked them. The PDF is rebuilt whenever the list changes. The one choice is the page size: each image’s own, or an A4 or Letter sheet turned to match it.
A PNG keeps its pixels as one compressed stream, and PDF readers can read that stream as it is: the decompressor and the row filters PNG uses are both part of PDF. So a PNG without transparency is not decoded on its way in. The compressed data in the PDF is the data from your file, and the badge says it was not re-encoded. A palette, a single transparent colour, a colour profile and a 16-bit depth all come across as they are.
Transparency is where PDF and PNG part ways. A PNG keeps alpha inside each pixel; a PDF keeps it in a separate image, the soft mask, laid over the colour. A PNG with an alpha channel is therefore unpacked and stored as those two images, without loss and at its own bit depth, so every pixel and every level of transparency is what it was. The badge says exactly that — no quality lost, but not a copy of the bytes. An interlaced PNG is unpacked the same way, because PDF has no reader for that order of rows.
JPEG, HEIC and the other formats are taken too, each in the most faithful way PDF allows, and each file’s row says which happened. Nothing is uploaded: the images are read in this tab and the PDF is written here.
FAQ
5Does it lower the quality
No. A PNG either goes in as stored or is unpacked and stored without loss; either way every pixel is the one in your file, at its own bit depth. The only images compressed again are HEIC, AVIF and lossy WebP, if you add some, and their rows say so.
Is transparency kept
Yes, as a soft mask — the separate alpha image PDF uses. A reader shows the page’s white through the clear parts, just as it would show a transparent PNG placed on a white page.
How big is each page
By default, the size of the image at the resolution the PNG states in its header, or 72 pixels to the inch when it states none, which puts one pixel on one point. A4 and Letter put each image on a sheet of paper instead, fitted and turned to match. Either way the pixels are not resampled; the page only says how large to draw them.
Will the PDF be smaller than the PNGs
No, and that is on purpose. A PNG that goes in as stored adds only a few hundred bytes of page around its data; one that is unpacked is compressed again without loss, which can come out a little larger or smaller than the file. Nothing is thrown away to make the PDF smaller.
Are the images uploaded
No. The browser reads them from your disk and writes the PDF on this page. There is no upload endpoint on this site, so there is nowhere for a photo to go, and nothing about the images is logged.