PNG to PDF Converter Free, No Upload

How to use PNG to PDF

1. Drop your PNG files on the upload zone or click Choose Files. You can pick several at once, and each file can be up to 150 MB.

2. Check the thumbnails. Use + Add More PNGs to add files, or the remove button on a thumbnail to take one out. Pages follow the order shown.

3. Click Convert to PDF. When it finishes, click Download File to save png_combined.pdf, or Preview Document to check it first.

Key features of PNG to PDF

🖼️ One page per PNG

Each PNG becomes its own page, sized to the image's pixel dimensions, so nothing is cropped, scaled or padded with margins.

🎨 Lossless, with transparency

pdf-lib decodes the PNG and stores the pixels without lossy compression, so there are no JPEG artifacts. Transparent areas stay transparent in the PDF.

🔒 Nothing is uploaded

The images are read and combined by JavaScript in your browser. Nothing is sent to a server, and there is no account or watermark.

About PNG to PDF

PNG to PDF creates a new document with pdf-lib and embeds each file with its embedPng method, which keeps the alpha channel. Every page is given the width and height of its image, so a 1920 by 1080 pixel screenshot becomes a 1920 by 1080 point page. Pages follow the order in which you added the files.

It suits screenshots, diagrams, logos and scanned line art, where PNG's sharp edges matter and JPEG artifacts would show. Because the pixels are stored without lossy compression, a PDF made from large PNGs can be big; the tool does not resize or compress images and has no page size option. Only PNG files are accepted here; for photos in JPG format use the JPG to PDF tool.

When to use PNG to PDF

You are filing a bug report or a test record and have a folder of app screenshots. Select them in the order the steps happened and each one becomes a page at its exact pixel size, so small interface text stays readable. Screenshot names usually contain the time they were taken, which makes picking them in order simple.

A form portal wants your logo, a signature or a stamp as a PDF. A transparent PNG keeps its alpha channel here, so the result can later be placed on another document without a white box around it. For that placing step use PDF Add Image.

You exported a flowchart, a wireframe or a chart from a design tool as a PNG at 2x scale for printing. The pixels are stored losslessly, so thin lines and small labels do not pick up JPEG blur, which makes this the right route for line art.

For photographs, JPG to PDF gives a far smaller file, and it also accepts PNG, so use it when a batch mixes both formats. To pull pages out of a PDF as images, the reverse direction, use PDF to PNG. To put several screenshots on one page, this is not the tool: each image always gets its own page.

Tips and troubleshooting

The file picker lists only .png files, but drag and drop does not check the type. A JPG dragged onto the zone is accepted, then fails at conversion with the message Failed to convert PNGs, and the whole batch stops. Use JPG to PDF for such files.
A file over 150 MB is refused with the message File name is too large and nothing from that selection is added. Choose the remaining files again without it.
Expect an output in the same range as the PNG files themselves: the pixel data is recompressed losslessly, and an image with transparency also stores its alpha channel as a separate mask.
A screenshot from a high-density display is stored at 2x, so a 1440 by 900 screen produces a 2880 by 1800 point page. Nothing is scaled down; viewers fit it to the window.
Add More PNGs appends to the current list, and the same file added twice appears twice. Remove the duplicate with the button on its thumbnail before converting.
The pages cannot be reordered by dragging the thumbnails. Add the files in the order you want, or move pages afterwards with Reorder Pages.
The download is named png_combined.pdf whatever the input names were. The result card shows its size before you save it.
Text in a screenshot is part of the picture, so the PDF cannot be searched until it goes through OCR PDF. How to make a scanned PDF searchable explains the steps and what affects accuracy.

How PNG to PDF works in your browser

The files you add are kept as File objects and shown as thumbnails through local object URLs. When you click Convert to PDF, pdf-lib creates a new document and each PNG is read into memory and given to embedPng. pdf-lib decodes the PNG itself, in JavaScript, and writes the pixels into the PDF as a Flate-compressed image object; if the PNG has transparency, the alpha channel becomes a soft mask attached to that image. A page is added with the image's width and height and the image is drawn across it.

After the last image the document is saved to bytes, wrapped in a Blob and offered on the result card. Download File creates a temporary blob URL for the browser to save; Preview Document shows the same Blob in a frame using your browser's PDF viewer. The page fetches pdf-lib from cdnjs.cloudflare.com when it opens, and no image data is sent over the network. The PNG files, the decoded pixels and the finished PDF stay in the tab's memory and are gone when you close it.

Frequently asked questions

Can I combine several PNG files into one PDF?

Yes. Select several files at once, or click + Add More PNGs after the first batch. Each PNG becomes one page in a single PDF, in the order you added them.

Is transparency kept?

Yes. The alpha channel is carried into the PDF, so transparent areas show whatever is behind them, which in most viewers is a white page.

Why is the PDF larger than my PNG files?

The pixels are stored without lossy compression, and a page is created for every image at full size. For a smaller file, convert the images to JPG first and use the JPG to PDF tool.

Can I mix PNG and JPG files in one batch?

Not here. The picker lists only PNG files, and a JPG dragged onto the zone makes the conversion fail. JPG to PDF accepts both formats in the same batch, so use it for a mixed set.

Why did the conversion fail with an error?

The message Failed to convert PNGs appears when a file is not real PNG data: a JPG dragged onto the zone, an image renamed to .png, or a damaged download. Leave that file out and try again, or convert it with JPG to PDF or Scan to PDF.

Does it work on a phone or tablet?

Yes. The page works in a mobile browser and Choose Files opens the device's file or photo picker. Everything is built in the device's memory, so keep batches of large images small.