PDF versions

Over the years the Portable Document Format has evolved enormously. This page lists all the major releases, starting from PDF 1.0 which was released in 1993. For each PDF version, the new features are listed. A more elaborate overview of the history of PDF can be found here.

Overall the PDF file format is remarkably flexible: obviously it is forward compatible, allowing you to open an old PDF 1.0 file in the latest version of the Adobe Reader. Backward compatibility is also pretty good: a recent PDF 1.7 file can be opened by Acrobat 4. The older software will ignore the newer features and may not be able to display page elements that use them.

PDF 1.0

Availability: November 1992 (announcement)/June 1993 (first software)
Matching software: Adobe Acrobat 1.0

PDF 1.1

Availability: November 1994
Matching software: Adobe Acrobat 2.0
New features:

  • External links – embed a link to external documents or URLs.
  • Article threads – articles that span multiple columns or pages are linked so that readers can easily navigate the text.
  • Security features- protect PDF files by a password.
  • Device-independent color – PDF 1.0 only supported RGB, which left quite some room for improvement.
  • Notes

PDF 1.2

Availability: November 1996
Matching software: Adobe Acrobat 3.0
New features:

  • Forms – allow users to add data to a PDF or use a PDF as an electronic form.
  • Unicode – use extended character sets.
  • Multimedia features – adding interactive page elements such as mouse events and support for additional multimedia types.
  • Support for the OPI 1.3 specifications
  • Improved color support – both the CMYK color space and spot colors can be used.
  • Halftone functions, as well as overprint instructions, can be embedded.

PDF 1.3

Availability: April 1999
Matching software: Adobe Acrobat 4.0
New features:

  • 2-byte CID fonts
  • Support for OPI 2.0
  • Additional color spaces – ICC-based colors are supported. A new color space called DeviceN improves support for spot colors.
  • Smooth shading, a technology that allows for efficient and very smooth blends (transitions from one color or tint to another).
  • Annotations
  • Digital signatures
  • JavaScript actions
  • RC4 encryption – 40 bit (Acrobat 4) & 56 bit (Acrobat 4.05)

PDF 1.4

Availability: May 2001
Matching software: Adobe Acrobat 5.0
New features:

  • Transparency
  • Improved support for JavaScript, including JavaScript 1.5 and better integration with databases.
  • Support for Tagged PDF – Tagged PDF files also contain structural information about the data that are represented by the PDF document. This means that meta-information like defining titles, blocks of text,… can be part of a PDF-document.
  • JBIG2 compression
  • 128-bit RC4 encryption

PDF 1.5

Availability: April 2003
Matching software: Adobe Acrobat 6.0 & Adobe Reader 6.0
New features:

  • Improved compression techniques including object streams & JPEG 2000 compression
  • enhanced XRef table – XRef streams, support for more objects,…
  • Support for layers
  • Improved support for tagged PDF
  • XFA – XFA is the abbreviation to XML Forms Architecture.
  • 12 additional transitions when using PDF pages for presentations.

PDF 1.6

Availability: January 2005
Matching software: Adobe Acrobat 7.0 & Adobe Reader 7.0
New features:

  • NChannel – an extension of the DeviceN mechanism for defining spot colors.
  • AES encryption
  • Some minor enhancements to annotations and tagging
  • Direct embedding of OpenType fonts – these no longer have to be embedded as TrueType or  Type 1 fonts.
  • PDF 1.6 files can be used as a kind of ‘container’ file format by offering the possibility to embed files into a PDF.
  • Embedding 3D data (U3D) – a useful addition for engineers but also for the packaging and display markets.
  • XML forms

PDF 1.7

Availability: October 2006
Matching software: Adobe Acrobat 8.0 & Adobe Reader 8.0
New features:

  • Improved support for commenting and security.
  • Add comments to 3D-objects and more elaborate control over 3D animations.
  • Embed default printer settings such as paper selection, the number of copies, and scaling.

Adobe extension levels

After PDF 1.7 Adobe handed over the PDF standard to the ISO organization, which meant they could no longer release new versions of the file format. To still have the ability to extend it, they added custom features to PDF that only their own software supports.

I for one welcome our new PDF overlords

Extension level 3

Availability: 2008
Matching software: Adobe Acrobat 9.0 & Adobe Reader 9.0
New features: 256-bit AES encryption

Extension level 5

Availability: 2009
Matching software: Adobe Acrobat 9.1 & Adobe Reader 9.1
New features: XFA 3.0 – an update for the XML Forms Architecture.

PDF 2.0 (ISO 32000-2)

Availability: August 2017
New features:

  • Each page in a PDF 2.0 file can have a separate output intent. That can, for example, be practical if a single PDF contains all the pages of a magazine for which the cover will be printed on a sheetfed offset press on glossy stock and the inner pages on a different press on matte paper. It is also handy when you merge two PDF files that each have a different output intent. With PDF 2.0 all the pages can keep their original output intent.
  • There is more freedom to define the halftones that have to be used for screening the entire page or certain page elements. This can be handy in processes that make use of special types of custom screening, such as flexo or gravure printing.
  • Transparency will be handled more consistently, especially when combining multiple PDF files with different output intents on a single press sheet. The more explicit way in which transparency handling is defined in the PDF 2.0 specifications should lead to better consistency across vendors: the output from the RIP of vendor A should match that of the workflow of vendor B.
  • Tagged PDF is a technology that has been part of the PDF specifications since version 1.5. It allows applications to better define the structure of the data such as the text flow. In PDF 2.0 a lot of work has been put in extending the Tagged PDF specifications. This may help with editing PDF 2.0 files since editing tools can use the structural data for modifying the PDF content.
  • Spot colors can be specified using spectral data. This is done using the CxF/X-4 standard and it should lead to more accurate proofs, especially when spot colors are printed on top of other page content.
  • A PDF 2.0 file can contain information about the order in which inks will be applied during the printing process. The ink order lay down data can help improve proofing accuracy.
  • PDF 2.0 files can contain more information on how an application or device should process the files, including control over black point compensation. In most workflows, however, it is the workflow software itself that takes care of job ticketing.
  • If you are dealing with confidential information, it can be useful to know that PDF 2.0 adds support for secure AES-256-bit encryption.
  • There are additional 3D capabilities, such as embedding 3D measurements or cross-section data. This can be useful in packaging or point-of-sale applications.

27 thoughts on “PDF versions

  1. Printed (Save as PDF) a form from my browseer (Chrome).
    PDF Info says:
    Creator: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/100.0.4896.88 Safari/537.36
    Producer: Skia/PDF m100
    version 1.4

    The PDF is not searchable, looks like it is just an image.
    But until past week the same form was searchable, I could copy values etc. from the PDF and save them to another file.

    What could be the explanation for the change?

  2. 1.2 is still compatible with all the PDF-readers I know: QPDFView, Evince, Acroread (Linux), as well as a current Firefox extension or -plugin.

  3. 1. Which PDF/X version is best for RGB to CMYK conversion, and converting all images to 300 DPI from low and high DPI images?
    2. What is the latest PDF/X version?
    3. Can PDF/X conversion be added to smartphone apps?
    Thank you.

  4. Ik heb een probleem met een pdf naken voor de drukker. Het bestand, het gaat over ons voorgeslacht met vele foto’s, heb ik gemaakt in Word. Maar nu kom ik tot de ontdekking dat Word de foto’s, al heb ik ze in grijswaarden opgeslagen, toch weer omzet in kleur. Het pdf bestand wat ik er dan van maak is dan ook kleur al is alles grijs. En wat gaat er dan gebeuren? De drukker gaat dat printen op een digitale printer (omdat de oplaag klein is) en dan zijn vele foto’s donker en wazig.
    Nu vindt ik op internet dat je een pdf kunt maken met grijstinten. of dat de oplossing is om de foto’s met tekst goed te laten drukken, moet ik nog ondervinden. Heeft iemand daar ervaring mee?
    Nu kan ik ook bij het PDF maken een aantal “codes” meegeven. Ik begrijp nu uit de uitleg hierboven dat het diverse versies zijn. Ik kan dan kiezen: PDF 1,5 tot en met PDF 2.0 en PDF/A-1b tot en met PDF/A-3u. Welke instelling zou ik moeten gebruiken om naar een drukker te sturen? Ik vroeg het aan de drukker, maar die zegt: gewoon een standaard pdf.

    1. Zie
      https://github.com/GerHobbelt/the-perils-of-Word-when-publishing-your-book#ms-word-en-aanpalende-ellende

      (Da’s halverwege de pagina; de rest is in ‘t Engels)

      Geen zin om dat pad te volgen, geen punt. Dan is ‘t antwoord: “PDF 1.7”. Dat kan iedereen wel zo’n beetje aan tegenwoordig.

      (En PDF met grijstinten dan? Dat zal wat *verandering* brengen, maar zal niet veel helpen, verwacht ik. Vermoedelijk begint de ellende al met de scans van de foto’s en/of nabewerkingen die je er op hebt uitgevoerd.)

  5. I have a lot of musical note pages in, as it seems to, which cannot be displayed in various pdf readers in my new tablet, even they have been shown successfully on my computer.
    Is there a tool to cope with this problem.

  6. Here is My Question: How to Change a RGB-PDF to a CMYK-PDF by code(or commandline),and, does it affected by pdf version, my using version is 1.4

    1. Callas pdfToolbox might meet your requirements. I’m not sure if it will do the conversion without affecting the version. Nowadays PDF 1.4 is pretty outdated.

  7. I have a problem with PDF’s created with ms Word on a mac. If the word uses shades , and transparanty the print is wrong.When the same word document is used to create a pdf with PC the pdf is printed correctly. Is this becuase of the quartz pdf context?
    Thank you for helping out

    1. There shouldn’t be, as image resolution is determined by your source files and application settings. The PDF version does not affect image resolution. Why you would want to stick to an ancient file format like PDF 1.4 is another matter.

  8. Thank you for this summary — it’s been very helpful in explaining why PDF v1.6 is giving me much more consistent results across multiple workstations when outputting identical files with identical jobOptions.

    1. I am not aware of any software that can do this. PDF 1.0 is simply too old – I think PDF 1.3 or 1.4 are the oldest versions that some apps still support. Converting to such an old standard is also difficult: what do you do with all the things present in your PDF files that are not possible within a PDF 1.0 file, such as transparency or current font formats?

    2. Using ghostscript I managed to output pdf 1.1 but couldn’t get to 1.0. Specifying 1.0 as the output format still generated 1.1

      gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.0 -dNOPAUSE -dBATCH -o out.pdf in.pdf

  9. Do you know of any software applications that can produce PDF 2.0 documents as of August 2019?

    I just tried with MS Word on Mac, and it was version 1.7. Pages on the same Mac created a PDF to the 1.4 spec!!

    1. yes, look for ghostscript. It’s mostly a command line tool, but I guess there are GUIs available. You can convert any PDF to any version. Also, look for mutool, it’s good to repair PDFs and sometimes good to use both in companion, so you can fix and convert the files.

  10. Need to understand what version of PDF was supported with the Adobe PDF Print Engine APPE 2.6 and APPE 3.8.

  11. Thanks for the breakdown.

    Can Adobe Acrobat DC from after the PDF 2.0 era work with forms created in Acrobat 8 (PDF 1.7 with no extensions)?

  12. Hi, I have a question. From which PDF version was possible to copy-paste part of the text included in the PDF file? I mean, I remember, if I’m not wrong, that before copy-paste a certain line of text was impossible. So from when was this possible to do?

    Many thanks..

    1. That has been possible for as long as I remember. What has improved over time is the ability to select a block of text.

  13. Hi, I have a question here.
    Will it affected the space between the paragraph if using different version of PDF to download or print out the documents.
    Example, if i open and print the file by using my laptop and using my handphone to do the same things, will it be a differences?
    If yes, is it because of the version of PDF?

    1. If you open a PDF file on your laptop and then open that same file on your phone, you’re looking at the same data, not at different versions of the PDF or PDFs with a different version.
      Can two applications display a PDF differently? Theoretically they shouldn’t, but in practice, they can.
      – One reason might simply be limitations or bugs in a PDF viewing application. If you open a recent PDF with an old viewing application, the program might not be able to interpret all the functions that newer versions of PDF can use. Some page elements might simply not be shown. This is the reason why in graphic arts it is customary to always use Adobe Reader or Adobe Acrobat. Those applications have proven to be the most reliable for correctly displaying complex PDF files. Other software can be just as good when it comes to viewing simple office documents but for print-ready PDF files used by designers, creative agencies and printers, the Adobe software is the way to go.
      – Settings within applications can be another reason you see the PDF in different ways. If you open a PDF in one copy of Adobe Acrobat that is configured to show overprints and then in another copy on another machine where that setting is disabled, some text or other elements may be shown differently. So even Acrobat must be configured correctly, otherwise what you see is not what you’ll get afterwards in print.
      – The PDF document itself can also cause problems. If it is not created correctly and has missing font data, one viewer might use font A to display the text and another PDF viewer might use font B. Missing font data is typically the reason why the spacing between characters on a line of text looks different in two different PDF viewers. I have never actually seen the spacing between paragraphs, so the height between one line of text and the next one, change.

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