Skip to main content

PNG to PDF converter

Turn PNG screenshots and exports into one PDF. At Maximum quality the PNG is embedded byte-for-byte, so transparency survives instead of being flattened.

No watermarkFree & unlimited
All processing happens in your browser. No data is sent to any server.

PNG and PDF agree on more than people expect. PNG stores every pixel exactly and can mark pixels transparent; PDF can carry that same lossless image and reproduce the transparency with a soft mask. So at Maximum quality this page does not flatten anything: the PNG is embedded as it is, alpha included, and a page is drawn around it. That matters for the two things people actually convert — screenshots, where crisp text must stay crisp, and logos or UI exports with a transparent background that would otherwise turn into a white rectangle. Page size, orientation, margin, scaling and page order are all yours to set, and the whole document is written by JavaScript in this tab.

Key facts about PNG to PDF converter

Key facts about PNG to PDF converter
TransparencyKept at Maximum quality — pdf-lib embeds the alpha channel as a PDF soft mask (SMask), so a transparent background stays transparent
Lossless pathMaximum embeds the PNG's own deflate-compressed pixels; nothing is re-sampled and no text edge is softened
Lower quality settingsLow 60, Medium 80 and High 92 re-encode to JPEG through a canvas — which flattens transparency onto white and blurs sharp text edges
One page per imageEvery PNG becomes exactly one page, in list order
Page sizesA4, US Letter, US Legal, A3, A5, Fit to image (the page takes the PNG's pixel dimensions), or a custom box from 100 to 2000 pt
OrientationPortrait, Landscape, or Auto, which decides per image — useful for a mix of wide screenshots and tall mobile captures
MarginsNone (0 pt), Small (18 pt), Medium (36 pt), Large (54 pt) or a typed value; not applied when the page size is Fit to image
ScalingFit keeps the ratio inside the margins, Fill covers the page and clips the overflow, Stretch distorts to the box, Original draws 1 pixel per point
Screenshot sizingAt Original, a 1920 px wide screenshot is 1920 pt wide — wider than A4's 595 pt. Fit is what keeps a full-width screenshot on the page
File sizeA PDF of PNGs is roughly the sum of the PNGs; PNG does not compress screenshots as hard as JPEG does, so these files are larger than the JPG equivalent
This page takes PNG onlyOther formats are rejected with a message; Images to PDF handles a mixed folder including HEIC, WebP, BMP, GIF and TIFF
Not includedOCR, a selectable text layer, page numbering, or merging with an existing PDF — those are separate tools

What happens to your file

pdf-lib, a JavaScript library, writes the document inside this tab. Your PNGs are read with the File API, passed to pdf-lib's PNG embedder — which is what builds the soft mask that preserves alpha — and the finished bytes become a Blob and a temporary object URL for the download. Choosing a quality below Maximum adds one local step: a 2D <canvas> in the same tab paints the PNG onto white and re-encodes it as JPEG. Neither path makes a network request. No upload endpoint, no Pages Function, no queue. Disconnect from the internet after the page loads and it still works, which is the simplest way to check the claim. Nothing is kept after you close the tab.

About this tool

  1. 1

    Add the PNG files

    Drop them in or browse. Each one appears as a thumbnail in the order it will appear in the PDF.

  2. 2

    Set the page order

    Drag a thumbnail to move it, or hover and use the arrows. The X removes one without clearing the rest.

  3. 3

    Pick the page size

    A4 or Letter for print; Fit to image when the PDF is for screen only and you want the page to be exactly the screenshot. Auto orientation handles a mix of wide and tall captures.

  4. 4

    Adjust margin and scaling

    Margins are under Advanced options. Fit with a Small margin keeps a full-width screenshot readable and inside the printable area.

  5. 5

    Leave quality at Maximum

    That is the setting that keeps the PNG lossless and its transparency intact. Only drop it if the PDF has to fit a size limit — and expect a white background where the alpha was.

  6. 6

    Preview, then download

    The finished PDF is rendered in the page. Check a page with fine text at full zoom before you download it.

Specs & compatibility
Input.png (image/png), including 8-bit and 16-bit RGBA. Other extensions are refused before anything is written
OutputA single application/pdf file, PDF 1.7, named png-to-pdf.pdf
Enginepdf-lib 1.17 — embedPng for the lossless path (alpha becomes an SMask), drawImage for page geometry
Page unitsPDF points: 1 pt = 1/72 inch. A4 is 595.28 × 841.89 pt, Letter 612 × 792 pt
Transparent pagesPDF has no page background of its own, so a transparent PNG shows whatever the viewer paints behind the page — white in most readers
Large screenshotsThe lossless path has no size ceiling beyond memory; a re-encode is capped by the browser's canvas limit, roughly 16,384 px a side on Chromium
Browser supportChrome, Edge, Firefox and Safari on desktop and mobile; no extension, no install
OfflineWorks with the network off once the page has loaded
  • Screenshots are the classic case for PNG to PDF: the lossless path keeps one-pixel text strokes sharp, where a JPEG re-encode gives them the fuzzy halo everyone recognises.
  • If your PDF looks like it has a white background where you wanted transparency, the quality setting is below Maximum — that path flattens onto white by definition.
  • PNG files are big. If a screenshot bundle comes out too large to email, converting the screenshots to JPG first usually beats dropping the quality here.
  • For a UI logo sheet, Fit to image with no margin produces pages exactly the size of each asset, which is easier to review than a page of A4 white space.
  • A 16-bit PNG from a design tool embeds fine, but the file is twice the size for a difference you cannot see in a PDF viewer — export 8-bit if size matters.
  • Mobile screenshots are tall and narrow. Auto orientation will still give them a portrait page, so combine that with Fit and a small margin rather than Fill.
  • Lossless PNG embedding with transparency preserved as a PDF soft mask
  • A4, Letter, Legal, A3, A5, fit-to-image or custom page boxes
  • Portrait, landscape or per-image automatic orientation
  • Margin presets plus a typed value, and four scaling modes
  • Drag-to-reorder thumbnails and an optional title page
  • In-page PDF preview before download
  • Turning a sequence of screenshots into a step-by-step PDF for a bug report or a hand-over document.
  • Packaging exported UI assets or logos into one file for a client review, with the transparent backgrounds intact.
  • Building a PDF of charts exported as PNG from a notebook or BI tool, at print page size.
  • Collecting scanned pages saved as PNG into a single document in the right order.
  • Making a printable A4 version of a long web capture, scaled to fit inside the margins.
  • Preparing PNG design proofs as one attachment instead of a folder someone has to unzip.
Yes, at the Maximum quality setting, which is the default on this page. PDF represents transparency with a soft mask, and pdf-lib builds that mask from the PNG's alpha channel when it embeds the image, so a logo with a transparent background stays transparent inside the document. Be aware of what that means visually: PDF pages have no background of their own, so a fully transparent PNG will look white in most readers simply because the reader paints a white page behind it. If you lower the quality setting, the conversion goes through a canvas that flattens alpha onto white first — that is the one way to lose it here.
On the lossless path, yes — the pixels in the PDF are the pixels in your PNG, so a one-pixel text stroke is still a one-pixel text stroke. This is the main reason to convert screenshots as PNG rather than JPG: JPEG's block transform puts ringing artifacts along exactly the high-contrast edges that text is made of. If you lower the quality here you will see that effect, because those settings re-encode each image as JPEG.
Because PNG is lossless and this page keeps it that way. A full-screen PNG screenshot is often 300 KB to 2 MB, and the PDF is roughly the sum of them plus a little structure — a PDF is a container, not a compressor. If size is the binding constraint you have three options: lower the quality setting here (which re-encodes to JPEG and loses transparency), convert the PNGs to JPG first and use the JPG to PDF page, or run the finished document through the PDF compressor.
No. This page writes one image per page. A grid or contact-sheet layout is a genuinely different job — it needs its own cell, spacing and caption controls, and folding it in here would make the page size and margin settings ambiguous. Use an image collage tool to build the grid first, then bring the single result here if you want it as a PDF.
No. Reading the files, embedding them and saving the document all happen in this tab, and the download link points at a Blob held in page memory. There is no upload endpoint for this tool; the site's only server-side code is a small set of Pages Functions for network tools, which this is not. You can verify it by going offline after the page has loaded — the conversion still runs.
This is the PNG page, and its defaults are written for PNG: Maximum quality means lossless with transparency, which is a promise that does not apply to a JPEG. Mixing formats would make that description untrue for some of your pages. JPGs belong on the JPG to PDF page, and a mixed folder — including HEIC from an iPhone, WebP, BMP, GIF or TIFF — belongs on Images to PDF, which converts what it needs to.

Related tools

View all

Updated

We use anonymous analytics to improve ToolChamp. No personal data is stored or sold. Privacy Policy