PNG to PDF without losing a pixel

What PNG to PDF does

PNG to PDF puts your PNG pictures into one PDF, one picture per page, in the order of the cards. It is made for the pictures people usually have as PNG: screenshots from phones and computers, scans an app saved as PNG, charts, diagrams, and logos or signatures with a see-through background.

PNG is a lossless format: it keeps every pixel exactly. A good PNG to PDF converter should keep it that way, and this one does:

• Plain PNGs go in exactly as they are. A PDF can hold the same kind of compressed pixels a PNG holds, so a plain PNG's pixels are copied in unchanged, with nothing opened or saved again.
• The rest are stored again without loss. PNGs with see-through parts, and interlaced PNGs, are opened by your browser and stored again losslessly, with see-through parts turned white.
• Other pictures work too. JPG, WebP, GIF, BMP and AVIF can go in the same PDF, so a mix of screenshots and photos is no problem.

All of it happens inside your browser. Your pictures aren't uploaded, and there is no sign-up and no watermark.

What happened to our PNGs

We put the most common kinds of PNG through this page in Chrome on a computer, with Same as picture pages, and noted what the result said. The sizes are the ones the page showed:

Every PDF was ready in 1.0 second or less; the four big scans took the longest. We also had a different PDF reader (poppler) draw every page, and each one matched its picture.

Look at the sizes: a PDF of plain PNGs is about as big as the PNGs themselves, often within 1 KB. That is the sign that nothing was compressed again. The see-through pictures changed size a little, because they were stored again; the signature even got smaller.

PNGs with see-through parts

PNG can store pixels you can see through: the checkered background an editor shows around a logo, a signature or a cut-out photo. A PDF page is paper, though, so see-through parts become white, just as if you had printed the picture.

For most pictures this is exactly what you want. Our see-through signature came out as a clean blue signature on a white page, and the colour logo looked just as it does on a white website.

These PNGs can't go in as they are, because a PDF stores see-through parts differently. So your browser opens the picture, lays it on white, and the page stores the result again losslessly: every pixel you can see is kept. Two details:

• Pictures with no colour at all, like a black signature, are stored as grayscale, which keeps the PDF small.
• 16-bit PNGs with see-through parts are stored at 8 bits per colour, like almost every picture on a screen. You won't see a difference, but print shops that asked for 16-bit should get the original PNG.

Some PNGs carry a see-through layer even when every pixel is solid, as some apps and phones save them that way. They are stored again in the same lossless way, and the result line tells you so. Nothing is lost either way.

White logos and white text: a warning

A logo made for dark backgrounds often has white letters on a see-through background. On white paper, the white parts disappear. We tried it with our own white logo: in the PDF, the yellow "PDF" and the icon were there, but the white word "NoUpload" had vanished completely, white on white.

The same happens to white text or white lines in any see-through PNG, such as a slide graphic or a sticker. Before converting such a picture:

1. Use the version made for light backgrounds, if there is one. Most brands have both.
2. Or give the picture a background of its own. Open it in a photo editor, add a coloured layer behind it, and save it as a new PNG.
3. Check the card. The preview on each card shows the picture on white, so you can spot missing parts before you press Convert.

Screenshots to PDF

Screenshots are the most common PNGs, and a PDF is a good way to send several of them together: a train ticket and its booking page, a chat that runs over several screens, payment receipts for a claim, or the steps of a problem for a help desk.

1. Take the screenshots in order. The cards appear in the order you pick the files, and most phones name screenshots by date and time.
2. Choose them all at once at the top of this page, then drag any card that is out of place. The number on each card is its page number.
3. Keep Same as picture for reading on screens. Each page takes the shape of its screenshot, so a tall phone screenshot gives a tall page with nothing around it.
4. Convert. Plain screenshots go in exactly as they are. Some phones save screenshots with a see-through layer even though nothing is see-through; those are stored again without loss, and the result line says which happened.

In our test, two phone screenshots made a two-page PDF of 663 KB in 0.2 seconds. Each page was the shape of the phone's screen: our 1080 × 2400 screenshot became a page 134 × 297 mm, as tall as A4 but much narrower. On a phone, that reads just like scrolling through the screenshots.

For a form or for email, a screenshot PDF can still be too big. Our one-screenshot PDF of 482 KB went to 90 KB with Compress PDF to 100 KB, and the result said Good. A two-screenshot PDF of 663 KB went to 143 KB with our PDF compressor at Recommended.

Choosing the page size for PNGs

Each picture is scaled to fit its page and centred, never cropped or stretched. Which page size suits depends on the PNG:

• Phone screenshots: Same as picture. On A4, a tall, narrow screenshot is scaled down to the height of the page, leaving wide white strips on both sides, so on a phone screen the screenshot shows smaller.
• Computer screenshots and slides: Same as picture, or A4 with Landscape. A wide picture fills a landscape page well. Auto turns each page to suit its picture.
• Scans and typed pages saved as PNG: A4. They were A4 paper to start with, so A4 pages print at the right size. Leave the margin at None, because the scan already has the paper's white edge.
• Logos, signatures and charts for printing: A4 with a Small margin, so the picture keeps clear of the printer's edge.

If you need everything on one paper size for printing, pick A4 or Letter: every page then gets that size, whatever the shape of its picture. If the PDF is only for screens, Same as picture is usually best.

Scans saved as PNG

Some scanner apps and copiers save pages as PNG. That keeps the scan perfect, but PNG is a poor fit for the fine grain of paper and ink, so the files are big. Four A4 pages from our sample scan, saved as PNGs at 150 ppi, came to 11.1 MB, and the PDF made from them here was 11.0 MB, because every page went in as it was. Four grayscale pages came to 5.35 MB, and their PDF to 5.34 MB.

That is too big for most email attachments and every upload form, so plan on a second step:

The colour scan shrank by 94%, the same share as our original sample scan does at Recommended. The grayscale pages shrank less, by 54%. For a form with a limit, go straight to Resize PDF or Compress PDF to 100 KB: they aim at the size the form asks for.

If your scanner app lets you choose, saving scans as JPG or straight as PDF gives smaller files from the start. Keep PNG for scans of drawings and black-and-white text, where it does well.

PNG or JPG inside a PDF

Because plain PNGs and JPGs both go into the PDF as they are, the PDF is as big as the pictures you give it. So when you can choose the format of your pictures, the choice carries over to the PDF:

• A page that is mostly a photo: as a PNG it was 889 KB, and its PDF 888 KB. The same page as a JPG was 74 KB, and its PDF 75 KB, twelve times smaller and with no difference you could see.
• A bar chart: as a PNG it was only 12 KB, and its PDF 13 KB. Flat colours and sharp edges are what PNG does best.
• Screenshots of apps and websites: PNG keeps text and icons crisp at a reasonable size: 214 KB for our full computer screen.

A simple rule: photos as JPG, everything with text, lines or flat colours as PNG. If you have both kinds, mix them freely in one PDF: each goes in its own best way. Our mixed test of a signature, a screenshot and a form page went in as one 588 KB PDF, and the result said what happened to each.

If you have pages as PNGs because you converted them from a PDF, for example with PDF to PNG, those PNGs are plain and go back in exactly as they are.

Reading the result

When the PDF is ready, the result line says what happened, in plain words. These are the sentences you will see with PNGs:

• "Every picture went in exactly as it was, at full quality." All your PNGs were plain, and nothing was opened or saved again.
• "Your picture was stored again without any loss." The PNG had see-through parts or was interlaced. Every visible pixel is kept, and see-through parts are white.
• "2 pictures went in exactly as they were; 1 was stored again without any loss." A mix, as in our test with a see-through signature, a screenshot and a form page.

Under the name you also see the size of your pictures and of the PDF. When they are close, the PDF holds your pictures untouched. The PDF is named after the first picture, with the page count added for several, like screenshot-2026-3-pages.pdf. With A PDF each, you get one ZIP file named like png-to-pdf-3-files.zip, with a PDF named after each picture.

Charts, diagrams and handwritten notes

Besides screenshots, PNG is the usual format for anything drawn on a computer or tablet: a chart copied out of a spreadsheet, a diagram from a drawing app, a page of handwritten notes from a note-taking app, a floor plan or a slide exported as a picture. These have sharp lines and flat colours, so PNG keeps them small and crisp, and in a PDF they stay that way.

• To share on screens, keep Same as picture. A wide chart gets a wide page, and nothing around it.
• To print, pick A4 with a Small margin. Each drawing is scaled to fit the page and centred, never cropped.
• To combine with documents, make the PDF of drawings here, then join it with other PDFs in Merge PDF.

A drawing is only as sharp as its pixels. If a chart looks blocky in the PDF, export it again from its app at a larger size, such as twice the width, and convert the new PNG.

Problems and fixes

• Part of a picture is missing. It was white on a see-through background, so it vanished on the white page. See the warning about white logos.
• A screenshot is sideways. Press the turn button on its card until it stands upright, then convert again. Turning doesn't compress the picture again.
• Screenshots look small with lots of white around them. You picked A4 or Letter. Pick Same as picture for pages the shape of your screen.
• The PDF is too big. Your PNGs are big, usually because they are scans or photos. Compress the PDF afterwards, as in Scans saved as PNG.
• A card shows a warning. The browser couldn't open that file as a picture; it may be damaged or not really a PNG. It is left out and the other pictures still convert. Open it in a photo app, save it again as PNG and add it again.

Finding your PNGs on each device

• Android

  Screenshots are in the Screenshots album of your gallery, or the Screenshots folder in your files. Tap Choose PNG files and pick several at once.

• iPhone and iPad

  Screenshots are in the Photos app, in the Screenshots album. Tap Choose PNG files, then Photo Library, and select them in order.

• Windows and Mac

  On Windows, screenshots saved with Windows key + Print Screen go to Pictures, Screenshots. On a Mac they land on the desktop. Drag them onto this page.

The PDF goes to your Downloads folder, or to Downloads in the Files app on an iPhone.

Private by design

Screenshots are among the most private pictures on a phone: chats, bank apps, payment receipts, tickets with your name and booking number. With this page they never leave your device. The pictures are put into the PDF by your own browser, and the page is not allowed to send data to any other website.

You can check it: once the page has loaded, switch off Wi-Fi and mobile data and make your PDF. It still works. The PDF records only that NoUploadPDF made it, and when; there's no account and no watermark. Our privacy policy has the details.

Limits

• See-through parts become white, and white parts of a see-through picture disappear on the white page.
• PNGs that have to be stored again are limited to 64 megapixels, or 16 megapixels on iPhone and iPad, and larger ones are scaled down. Plain PNGs have no such limit.
• 16-bit PNGs with see-through parts are stored at 8 bits per colour.
• Text in a screenshot stays part of the picture: you can read it, but not search or copy it in the PDF.
• The page doesn't crop or edit pictures. Crop status bars or other parts in your photo app first.
• A PDF of PNG scans is big. Compress it afterwards, as shown above.