What is a PDF file?
PDF stands for Portable Document Format. It was created by Adobe and first released in 1993. A PDF fixes the layout of every page so it looks the same on any device. Converting a PDF to an image renders each page to pixels; converting an image to PDF wraps it as a page.
| Type | document |
|---|---|
| Compression | Lossy or lossless |
| Colour | any colour, pages can mix text, vectors and images |
| In a browser | opens in every browser's built-in viewer |
| Common uses | documents, forms, invoices and print-ready files |
| MIME type | application/pdf |
Which format should you convert PDF to?
- PDF to JPG to share a page as a photo.
- PDF to PNG to keep text on a page sharp.
- PDF to TIFF for print and archive workflows.
PDF is lossy or lossless depending on how it was saved, so check what a program needs before converting.
How to open a PDF file
Whether a PDF file opens with a double click depends on the device. Here is what works on each, without buying software:
| Windows | Edge opens PDF files directly, as does any PDF reader. |
|---|---|
| Mac | Preview opens most image formats and PDF files; Quick Look (press the space bar in Finder) shows a preview without opening an app. |
| iPhone and iPad | The Files app and Photos show common image types and PDF files. Other formats need an app, or converting here. |
| Android | Google Photos and Files by Google open common images and PDFs. Other formats need a viewer app, or converting here. |
| Web browser | PDF opens in every browser's built-in viewer. |
Want the technical details? See what a .pdf file is, with its MIME type, file signature and a viewer.
PDF compared with other document and image formats
How PDF stacks up against the formats people most often convert it to or from:
| Format | Compression | Transparency | Released | Best for |
|---|---|---|---|---|
| Either | No | 1993 | documents, forms, invoices and print-ready files | |
| JPG | Lossy | No | 1992 | camera photos, web images and email attachments |
| PNG | Lossless | Yes | 1996 | screenshots, logos, diagrams and anything with transparency |
How to use the PDF converter
- Choose the format you want in the Convert to menu.
- Drop your PDF files on the box, or press Choose PDF files. Several files can go in at once.
- Adjust the settings if you need to; the defaults suit most people.
- Press Convert and save each file with its Download button. Converting to AVIF, AZW3, DXF, EMF, EPUB, HEIC, HEIF, MOBI, PDB, PSD, WMF uses our server, which deletes the file right after; the rest never leave your device.
Tips for converting PDF files without losing quality
PDF can be lossy or lossless depending on how the file was saved. Either way, converting to a lossless format keeps exactly what is there, and converting to a lossy one trades a little detail for a much smaller file.
- Pick the resolution by purpose: 72 dpi for screen previews, 150 dpi for reading, 300 dpi when text must stay crisp in print.
- Use PNG for pages with text and diagrams, and JPG for scanned photos, to keep the files small without blurring the text.
- Converting images to PDF gives one page per image, which is the format most forms and portals accept for attachments.
- Nothing in the PDF leaves your device: pages are rendered by PDF.js running inside this tab.
Convert PDF files from the command line
The pdftotext tool from Poppler extracts the text layer:
pdftotext -layout input.pdf output.txtThe converter on this page does the same job in your browser, without installing anything.
PDF converter FAQ
What is a PDF file?
PDF stands for Portable Document Format, a document format created by Adobe in 1993. A PDF fixes the layout of every page so it looks the same on any device. Converting a PDF to an image renders each page to pixels; converting an image to PDF wraps it as a page.
How do I open a PDF file?
PDF opens in every browser's built-in viewer. If the program you need will not open it, convert it to a more widely supported format above.
What is the most common PDF conversion?
PDF to TXT is the conversion people search for most. The text layer of each page is extracted in order, with a blank line between pages.
Does converting PDF files here upload them?
Only for some conversions. Converting to AVIF, AZW3, DXF, EMF, EPUB, HEIC, HEIF, MOBI, PDB, PSD, WMF uses our conversion server, where the file is deleted as soon as the result is sent back; the other conversions run inside your browser and never leave your device.
Is the PDF converter free?
Yes. There is no sign-up and no watermark. Conversions that use our server accept files up to 25 MB, with a fair-use limit per hour. The site is supported by advertising.
Can I convert PDF files on iPhone or Android?
Yes. Open this page in Safari on iPhone and iPad, or in Chrome on Android, choose your PDF files and download the results to your Downloads folder.
Can I convert several PDF files at once?
Yes. Drop as many as you like; they are converted one after another, each with its own download button.