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Posted 1 Dec 2005


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Converting PDF to Text in C#

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4.80/5 (143 votes)
19 Apr 2015CPOL3 min read
Parsing PDF files in .NET using PDFBox and IKVM.NET (managed code).


April 20, 2015: The article and the Visual Studio project are updated and work with the latest PDFBox version (1.8.9). It's also possible to download the project with all dependencies (resolving the dependencies proved to be a bit tricky).

February 27, 2014: This article originally described parsing PDF files using PDFBox. It has been extended to include samples for IFilter and iTextSharp.

How to Parse PDF Files

There are several main methods for extracting text from PDF files in .NET:

  • Microsoft IFilter interface and Adobe IFilter implementation.
  • iTextSharp
  • PDFBox

None of these PDF parsing solutions is perfect. We will discuss all these methods below.

1. Parsing PDF using Adobe PDF IFilter

In order to parse PDF files using IFilter interface you need the following:

Sample code:

using IFilter;

// ...

public static string ExtractTextFromPdf(string path) {
  return DefaultParser.Extract(path); 

Download a sample project:

If you are using the PDF IFilter that comes with Adobe Acrobat Reader you will need to rename the process to "filtdump.exe" otherwise the IFilter interface will return E_NOTIMPL error code. See more at Parsing PDF Files using IFilter [].


  1. Using unreliable COM interop that handles IFilter interface (and the combination of IFilter COM and Adobe PDF IFilter is especially troublesome).
  2. A separate installation of Adobe IFilter on the target system. This can be painful if you need to distribute your indexing solution to someone else.
  3. You have to use "filtdump.exe" file name for your application with the latest PDF IFilter implementation that comes with Acrobat Reader.

2. Parsing PDF using iTextSharp

iTextSharp is a .NET port of iText, a PDF manipulation library for Java. It is primarily focused on creating and not reading PDFs but it supports extracting text from PDF as well.

Sample code:

using iTextSharp.text.pdf;
using iTextSharp.text.pdf.parser;

// ...
public static string ExtractTextFromPdf(string path)
  using (PdfReader reader = new PdfReader(path))
    StringBuilder text = new StringBuilder();

    for (int i = 1; i <= reader.NumberOfPages; i++)
        text.Append(PdfTextExtractor.GetTextFromPage(reader, i));

    return text.ToString();

Credit: Member 10364982

Download a sample project:

You may consider using LocationTextExtractionStrategy to get better precision.

public static string ExtractTextFromPdf(string path)
  ITextExtractionStrategy its = new iTextSharp.text.pdf.parser.LocationTextExtractionStrategy();
  using (PdfReader reader = new PdfReader(path))
      StringBuilder text = new StringBuilder();

      for (int i = 1; i <= reader.NumberOfPages; i++)
          string thePage = PdfTextExtractor.GetTextFromPage(reader, i, its);
          string[] theLines = thePage.Split('\n');
          foreach (var theLine in theLines)
      return text.ToString();


Credit: Member 10140900

Disadvantages of iTextSharp:

  1. Licensing if you are not happy with AGPL license

3. Parsing PDF using PDFBox

PDFBox is another Java PDF library. It is also ready to be used with the original Java Lucene (see LucenePDFDocument).

Fortunately, there is a .NET version of PDFBox that is created using IKVM.NET (just download the PDFBox package).

Using PDFBox in .NET requires adding references to:

  • IKVM.OpenJDK.Core.dll
  • IKVM.OpenJDK.SwingAWT.dll
  • pdfbox-1.8.9.dll

and copying the following files the bin directory:

  • commons-logging.dll
  • fontbox-1.8.9.dll
  • IKVM.OpenJDK.Text.dll
  • IKVM.OpenJDK.Util.dll
  • IKVM.Runtime.dll

Using the PDFBox to parse PDFs is fairly easy:

using org.apache.pdfbox.pdmodel;
using org.apache.pdfbox.util;

// ...

private static string ExtractTextFromPdf(string path)
  PDDocument doc = null;
  try {
    doc = PDDocument.load(path)
    PDFTextStripper stripper = new PDFTextStripper();
    return stripper.getText(doc);
  finally {
    if (doc != null) {

Download a sample project:

The size of the required assemblies adds up to almost 18 MB:

  • IKVM.OpenJDK.Core.dll (4 MB)
  • IKVM.OpenJDK.SwingAWT.dll (6 MB)
  • pdfbox-1.8.9.dll (4 MB)
  • commons-logging.dll (82 kB)
  • fontbox-1.8.9.dll (180 kB)
  • IKVM.OpenJDK.Text.dll (800 kB)
  • IKVM.OpenJDK.Util.dll (2 MB)
  • IKVM.Runtime.dll (1 MB)

The speed is not so bad: Parsing the U.S. Copyright Act PDF (5.1 MB) took about 13 seconds.

Thanks to bobrien100 for improvements suggestions.


  1. IKVM.NET Dependencies (18 MB)
  2. Speed (especially the IKVM.NET warm-up time)

Related information


  • April 20, 2015 - Updated to work with the latest PDFBox release (1.8.9)
  • November 27, 2014 - Updated to work with the latest PDFBox release (1.8.7)
  • March 10, 2014 - IFilter file name limitations added, iTextSharp sample extended
  • February 27, 2014 - Samples for IFilter and iTextSharp added.
  • February 24, 2014 - Updated to work with the latest PDFBox release (1.8.4)
  • June 20, 2012 - Updated to work with the latest PDFBox release (1.7.0)


This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)


About the Author

Dan Letecky
Czech Republic Czech Republic
My open-source event calendar/scheduling web UI components:

DayPilot for JavaScript, Angular, React and Vue
DayPilot for ASP.NET

Comments and Discussions

QuestionIssue with "Pdf2Text" Pin
Paul G. Scannell24-Aug-21 4:34
MemberPaul G. Scannell24-Aug-21 4:34 
GeneralMy vote of 3 Pin
geoatif12-Apr-20 21:50
professionalgeoatif12-Apr-20 21:50 
Questionsite to download complete solution unavailable Pin
Kiebor29-Aug-19 0:05
MemberKiebor29-Aug-19 0:05 
Questionnot working Pin
ahdk21-Mar-19 2:04
Memberahdk21-Mar-19 2:04 
QuestionHow Can I highlight text in current program while speaking Pin
Member 1400088528-Sep-18 1:48
MemberMember 1400088528-Sep-18 1:48 
QuestionThe Document you are trying to load... Pin
Member 136566331-Feb-18 10:14
MemberMember 136566331-Feb-18 10:14 
QuestionThe program don't create the txt file Pin
Member 1274433921-Sep-16 17:57
MemberMember 1274433921-Sep-16 17:57 
QuestionHow I retrieve the text was extracted from the pdf file to manipulate it ? Pin
Member 1274433918-Sep-16 13:16
MemberMember 1274433918-Sep-16 13:16 
AnswerRe: How I retrieve the text was extracted from the pdf file to manipulate it ? Pin
Garth J Lancaster18-Sep-16 15:26
professionalGarth J Lancaster18-Sep-16 15:26 
GeneralRe: How I retrieve the text was extracted from the pdf file to manipulate it ? Pin
Member 1274433919-Sep-16 17:26
MemberMember 1274433919-Sep-16 17:26 
PraiseMY Vote is 5 Pin
Hassan Alrehamy17-Jun-16 16:41
MemberHassan Alrehamy17-Jun-16 16:41 
QuestionMessage Closed Pin
27-Nov-15 3:57
MemberEvale27-Nov-15 3:57 
GeneralRe: .NET component for converting? Pin
PIEBALDconsult27-Nov-15 3:58
professionalPIEBALDconsult27-Nov-15 3:58 
GeneralRe: .NET component for converting? Pin
Richard Deeming27-Nov-15 4:25
mveRichard Deeming27-Nov-15 4:25 
QuestionWhy copy to bin folder with PDFBox Pin
Gregory A. Beamer25-Nov-15 8:03
MemberGregory A. Beamer25-Nov-15 8:03 
QuestionHow to retrieve and store text and image from pdf file to sql in wpf using c# Pin
Aravindh Aravindhan30-Sep-15 1:21
MemberAravindh Aravindhan30-Sep-15 1:21 
QuestionConverting PDF to Text in C# ! " i need converting with formatting in Text file ? Pin
Member 1190699718-Aug-15 0:42
MemberMember 1190699718-Aug-15 0:42 
QuestionDoes this work with Windows Phone 8.1? Pin
Member 1104748424-Jul-15 3:29
MemberMember 1104748424-Jul-15 3:29 
QuestionParse Table in PDF Pin
Raj Reddy (INDIA)7-Jul-15 7:01
MemberRaj Reddy (INDIA)7-Jul-15 7:01 
QuestionWhat an article boss 5 out of 5 Pin
Arkadeep De24-Apr-15 8:02
professionalArkadeep De24-Apr-15 8:02 
AnswerRe: What an article boss 5 out of 5 Pin
Dan Letecky24-Apr-15 8:39
MemberDan Letecky24-Apr-15 8:39 
QuestionFull trust Pin
nicolaz021-Apr-15 21:30
Membernicolaz021-Apr-15 21:30 
AnswerRe: Full trust Pin
Dan Letecky24-Apr-15 8:40
MemberDan Letecky24-Apr-15 8:40 
GeneralMy vote of 5 Pin
richihu21-Apr-15 0:29
Memberrichihu21-Apr-15 0:29 
GeneralRe: My vote of 5 Pin
Dan Letecky24-Apr-15 8:41
MemberDan Letecky24-Apr-15 8:41 

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