What PDF version your file is, and why it matters

A PDF version number tells you which features and security settings that file can use. Older PDFs — versions 1.3 and below — cannot handle modern compression, transparency, or certain security protections. If you need to use your PDF with newer software, share it with someone whose reader requires a newer version, or add features that older versions don't support, you'll need to convert it up.

The conversion itself is straightforward: you open the file in software that can read and re-save PDFs, then export or save it as version 1.4 or higher. Version 1.4 is a good target because it's widely supported and handles most modern features. Versions 1.5 through 1.7 exist and offer additional capabilities, but 1.4 solves most compatibility problems.

You don't need to understand what each version does technically — you just need to know that converting up makes your PDF work with more tools and more recent computers, and that the process doesn't change what the document looks like or what it says.

Key Takeaways

  • Check your PDF's current version in Adobe Reader by opening File > Properties > Description, or in Preview on Mac by opening Tools > Show Inspector.
  • Adobe Acrobat (the paid desktop version) can convert PDFs by opening the file and using File > Save As > choose PDF version from the dropdown.
  • Free online converters like Smallpdf, ILovePDF, and PDF2Go let you upload a PDF and download it in a newer version without installing software.
  • Some free desktop tools like LibreOffice can open a PDF and export it as a newer version, though the process is less direct than paid software.
  • Converting up does not change the document's appearance or content — it only updates the technical format underneath.

Checking what version your PDF currently is

Before you convert, confirm that your PDF actually needs converting. Open the file in Adobe Reader (the free reader from Adobe), then go to File > Properties. Click the Description tab. You'll see "PDF Version" listed — it will show something like "1.3" or "1.5". If it already says 1.4 or higher, you're done.

On a Mac, open the PDF in Preview, then go to Tools > Show Inspector. The version appears in the inspector panel on the right side of the screen. On Windows, if you don't have Adobe Reader, right-click the PDF file, select Properties, and look for a Details tab — some Windows versions show the PDF version there, though not all.

Using Adobe Acrobat to convert the version

If you have Adobe Acrobat (the paid desktop application, not the free Reader), this is the most direct route. Open your PDF in Acrobat, then go to File > Save As. A dialog box will appear. Look for a dropdown menu that says "PDF Version" or "Format" — click it and select the version you want (1.4, 1.5, 1.6, or 1.7). Then click Save and choose where to store the new file.

Acrobat will create a new PDF in the version you selected. The original file stays unchanged. This method takes about 30 seconds and works reliably for any PDF that Acrobat can open.

Converting with free online tools

If you don't have Acrobat, several free websites let you upload a PDF and download it in a newer version. Smallpdf.com, ILovePDF.com, and PDF2Go.com all offer this feature. The process is the same on each: go to the website, click the button to upload your PDF, wait a few seconds for it to process, then download the converted file.

These tools work on any computer with a web browser and an internet connection. They're fast — usually under a minute from upload to download. The tradeoff is that you're sending your PDF to someone else's server, so don't use this method for sensitive documents like tax returns, medical records, or anything with personal information. If privacy is a concern, use a desktop tool instead.

Most of these sites let you convert one or two PDFs free per day, then ask you to pay for more. That's usually enough for occasional use.

Converting with LibreOffice or other free desktop software

LibreOffice is free software you can download and install on Windows, Mac, or Linux. It can open PDFs and export them in a newer version, though the process is less direct than Acrobat. Open LibreOffice Draw (the drawing component), go to File > Open, and select your PDF. The PDF will open as an editable document. Then go to File > Export as PDF. A dialog box will appear with export options — look for a dropdown that says "PDF Version" and select 1.4 or higher. Click Export and save the file.

This method keeps your file on your own computer and costs nothing. The downside is that LibreOffice sometimes changes the layout slightly when it opens a PDF, especially if the original uses complex formatting or embedded fonts. For simple PDFs with text and basic images, it works fine. For PDFs with precise layouts or special fonts, Acrobat or an online tool is safer.

What happens to your PDF after conversion

Converting a PDF to a newer version does not change what the document looks like or what it says. The text, images, and layout stay exactly the same. What changes is the technical format underneath — the new version can use more efficient compression, newer security features, and additional capabilities that older software might not recognize.

The file size may get slightly smaller after conversion because newer versions use better compression. In rare cases, if your PDF uses very old or unusual features, converting up might cause those features to behave differently in older software — but this is uncommon and usually not a problem.

When you might need to convert your PDF

You'll typically need to convert a PDF up if someone asks you to send them a file in version 1.4 or higher, if you're uploading it to a system that requires a newer version, or if you're trying to add security features (like password protection or permission restrictions) that only work in newer versions. Some older printers or scanners create PDFs in version 1.3, and if you need to use that file with modern software, converting up ensures compatibility.

If you're just reading a PDF or printing it, the version usually doesn't matter. Most modern software handles any version without problems. Convert only if you have a specific reason to do so.

Frequently Asked Questions

Will converting my PDF make it smaller or larger?

Usually smaller. Newer PDF versions use more efficient compression, so the file often shrinks by 10 to 30 percent. In rare cases with unusual content, the size might stay about the same. It won't get significantly larger.

Can I convert a PDF back to an older version if I need to?

Yes, the same tools work in reverse. You can convert a 1.7 PDF back down to 1.4 or 1.3 using Acrobat, online converters, or LibreOffice. However, if the PDF uses features only available in newer versions, converting down might remove or break those features.

Is it safe to use online PDF converters with private documents?

Most reputable sites (Smallpdf, ILovePDF) delete uploaded files after a few hours, but they do briefly store your file on their servers. If your PDF contains sensitive information like tax records or medical details, use a desktop tool like Acrobat or LibreOffice instead to keep the file on your own computer.

What if my PDF won't open in the conversion tool?

Try a different tool — some software handles corrupted or unusual PDFs better than others. If the file is password-protected, you may need to unlock it first. If it's scanned from paper, the tool might need a moment to process it. If nothing works, the PDF may be too damaged to convert, and you might need to rescan or recreate the document.