PNG to PDF: Lossless Image Conversion Without a Text Layer
This page lets you upload up to 20 PNG images and combine them into a single PDF document, with each image becoming one page of the PDF. The result is a purely visual document — the original pixels are preserved, but any text that was present in the PNG screenshots, diagrams, or artwork is unreachable for search, selection, or copying. Unlike a JPG-to-PDF or PDF-to-images tool, this page is designed specifically for converting from PNG to PDF, and it keeps the lossless quality of PNG files intact. All processing happens in your browser; nothing is uploaded to any server.
How the Conversion Works Under the Hood
When you select a set of PNG files, the tool decodes each one in the browser. It then constructs a new PDF document page by page, embedding each decoded image. Because the page champions lossless quality, every image is packed with lossless compression — no downsampling or JPEG re‑compression occurs, and the result is a PDF whose image content is visually identical to the source PNGs. Each page is sized to its image: a 1920×1080 screenshot becomes a 1920×1080-point page.
The PDF file itself is built entirely in memory on your device, then offered as a download. Because no text layer is created, a search engine or PDF reader will find zero textual content. If you need a searchable PDF from screenshots of text, you must run OCR on the output separately.
Why the absence of a text layer matters
Many users assume that because a PNG screenshot contains legible text, the resulting PDF will allow them to ctrl+f that text. That assumption is false. A PNG is a bitmap: it stores the colour of every pixel. When that bitmap is embedded into a PDF, it becomes a raster image object – the PDF viewer has no way to know which pixel groups form characters. The only way to get searchable text is to raster the image through an OCR engine, which this tool does not do. The output PDF carries no text layer — the text in the original PNG screenshots or diagrams becomes unreachable for search or copying.
Accepted Input Formats and Their Characteristics
This page is locked to PNG: the file picker filters to .png files, and every image you add becomes one page. PNG is the right source format for this job because it is lossless — screenshots, diagrams, logos, and text‑heavy images keep every pixel exactly as drawn. If your images are in another format (JPG, WebP, AVIF, GIF, HEIC, HEIF), the site’s Image to PDF page accepts all of those.
PNG stores pixels with lossless DEFLATE compression, so nothing is approximated or discarded. It supports full transparency and millions of colours, unlike GIF’s 256‑colour palette. The trade‑off is size: a photograph saved as PNG is several times larger than the same photo as JPG, which is why PNG is the format of choice for graphics with sharp edges, flat colour, and text rather than for photos.
Each file becomes one page, and the order of pages follows exactly the order you add the files. There is no way to re‑order images after adding them — if the sequence matters, name the files so they sort in the desired order and select them in one go.
Limits and Exact Error Messages
The tool enforces strict limits to prevent browser crashes and to keep processing manageable. The error messages are specific to each failure.
| Condition | Error message |
|---|---|
| No files selected | “Choose at least one file.” |
| More than 20 files chosen | “Choose up to ‹max› images at a time.” (where ‹max› = 20) |
| Any file larger than 80 MB | “Each file must be ‹max› or smaller.” (where ‹max› = 80 MB) |
| File is not an image (e.g., a .pdf or .docx) | “Choose image files: JPG, PNG, WebP, AVIF, GIF, HEIC or HEIF.” |
| File appears to be an image but cannot be decoded | “This image could not be decoded. It may be corrupted or not actually an image.” |
| File is zero‑bytes | “This file is empty.” |
| The conversion run fails unexpectedly | “Conversion failed. Try another file.” |
| Some or all files could not be processed | “‹count› file(s) could not be processed.” |
| A file’s type fails validation during conversion | “This file type is not supported for the selected direction.” |
The 20‑file limit and 80 MB per‑file cap keep the browser tab from running out of memory: decoding one very large image, say an 80 MB PNG at 100 megapixels, already consumes hundreds of megabytes of RAM. If you need to combine more than 20 images, run the tool twice and merge the two PDFs with a separate PDF merger, or split your batch.
Output and Download Details
After successful conversion, the page displays a results panel with these fields:
- “Created ‹count› PDF file.” – ‹count› is always 1 because the tool produces a single PDF document.
- “Source” – the total size of all input images, in bytes (formatted as KB, MB as appropriate).
- “Output” – the size of the created PDF, in the same unit.
- “Pages” – the number of pages in the PDF, which equals the number of successfully processed images.
- “Download” button – clicking it saves the PDF under the source image’s name for a single file (
scan.pngbecomesscan.pdf), or asbrobrogo-images.pdffor a batch. - Summary line – for example: “Created 12 page(s): 3.4 MB -> 4.1 MB”
The source vs. output size comparison can be surprising. A PNG compressed at a very high level may be smaller than the PDF that contains it because PDFs add structural overhead (page tree, image dictionaries, cross‑reference table). Because PNGs are packed losslessly, the output is usually close to the sum of input sizes plus a few kilobytes of overhead.
Privacy and Security: Why This Matters
All file processing occurs entirely on your device; nothing is uploaded. This is a significant advantage over online converters that send your images to a remote server. For sensitive screenshots, confidential diagrams, or proprietary artwork, you can use this tool without worrying about data leaving your network. The only requirement is a modern browser (Chrome, Firefox, Safari, Edge). No internet connection is needed after the page is loaded – you could even save the page for offline use.
Common Mistakes and Troubleshooting
1. Uploading files with wrong extensions
A.png file that is actually a renamed.jpg will fail at the decoding stage. The tool checks the file header during decoding, not the extension. If you get “This image could not be decoded,” first verify the file by opening it in a separate image viewer. If it opens there, the issue may be a temporary browser glitch – try refreshing the page.
2. Selecting PDF files as input
Because the page is “Images to PDF”, dropping a PDF file triggers the message “Choose image files: JPG, PNG, WebP, AVIF, GIF, HEIC or HEIF.” This is by design. To reverse the direction (PDF to images), you would need a different page on the same site.
3. Batch size too large
If you need to convert 30 images, you can do two batches of 15, then use a PDF merger tool. However, note that each batch produces a separate PDF; merging them later will add the merger’s own overhead.
4. Empty files
A file that is 0 bytes will never be processed. The tool checks file size immediately upon selection. If you see “This file is empty,” the file may have failed to download correctly. Re‑export from the original source.
5. Large file but within limits
A 79 MB PNG of, say, a high‑resolution scan may decode and convert, but it could strain browser memory. If you experience tab crashes, try resampling the image to a lower resolution before uploading.
Frequently Asked Questions
Can I add more than 20 images?
No. The tool’s front end enforces a hard limit of 20 files. If you try to select more, you get the message “Choose up to 20 images at a time.” If you need more, split your set into multiple batches and merge the resulting PDFs with another tool.
Why is my PDF not searchable?
Because the original PNG images are raster bitmaps with no embedded text. The tool does not perform OCR. The PDF contains the image pixels only, so any text in the screenshots or scans is inaccessible to search. To get searchable text, you must run an OCR application on the PDF output.
Does the tool reduce image quality?
No. This page accepts PNG only, and PNG images are packed losslessly — the pixels you get in the PDF are the pixels you uploaded. No downsampling or lossy re‑compression occurs.
Can I convert a PDF back to images on this page?
No. This page only accepts image files as input and produces a single PDF as output. The reverse direction (PDF to images) is handled by a separate page on the site. If you drop a PDF into this page, you will see “Choose image files: JPG, PNG, WebP, AVIF, GIF, HEIC or HEIF.”
Why is the output PDF larger than the sum of my input images?
Each PDF file contains structural overhead: page object definitions, image stream dictionaries, a cross‑reference table, and metadata. For a single image, this overhead is typically a few kilobytes. For many images, the overhead multiplies. For lossless PNGs, the output size is usually very close to the input total.
What happens if one file in a batch fails?
The conversion continues with the remaining images. The results list names the failed file together with the reason (for example “This image could not be decoded. It may be corrupted or not actually an image.”), and the status line reports how many files could not be processed. The PDF is still built from the images that succeeded, so you can download it and retry the failed file separately.