Merge PDF Files into One Document in C#

Wordize for .NET is a professional solution for automating PDF document merging within enterprise document workflows. The Merger class enables C# developers to programmatically combine PDF files for report preparation, documentation creation, and legal transaction support.

Key Features:

The Merge() method combines multiple PDF documents into a single file with automatic format detection based on file extensions
Precise formatting control during PDF merging with three main modes: complete style merging of all PDF documents, preserving original formatting of each source, or maintaining exact layout and page structure without changes
Export capability of PDF merge results to graphic format - the MergeToImages() method returns merge results as an array of images
Fluent API support for launching PDF merge operations through MergerContext and method chaining, enhancing C# code clarity

Use Cases:

Combine individual sections, chapters, or modules into unified reports and technical documents for convenient distribution
Merge PDF files from different departments or project participants into unified presentations
Create consolidated archives from related PDF documents for storage system optimization
Combine related PDF documents, appendices, and supplements into unified packages
Merge PDF content from various sources to create catalogs and reference materials

Test the capabilities of programmatic PDF document merging using the interactive online demo presented on this page. Upload multiple PDF files, specify their merge parameters, execute the operation, and download the consolidated document for review. The provided C# code snippet is fully ready for use in your .NET project.

Run code

Upload the first document

Upload other documents

Select output format from the list

using Wordize.Merging;

Merger.Merge("Output.pdf", 
    [
        "Input1.pdf", 
        "Input2.pdf" 
    ]);
                            using Wordize.Merging;

Merger.Merge("Output.pdf", 
    [
        "Input1.pdf", 
        "Input2.pdf" 
    ]);
                            using Wordize.Merging;
using Wordize.Saving;

var imageStreams = Merger.MergeToImages(
    ["Input1.pdf", "Input2.pdf"], 
    new ImageSaveOptions(SaveFormat.Pdf) { PageLayout = MultiPageLayout.Vertical(10) },
    MergeFormatMode.KeepSourceFormatting
);

using var file = File.Create($"Output.pdf");
imageStreams[0].Position = 0;
imageStreams[0].CopyTo(file);
                            using Wordize.Merging;
using Wordize.Saving;

ImageSaveOptions saveOptions = new ImageSaveOptions(saveFormat);
saveOptions.PageLayout = MultiPageLayout.Vertical(10);

Merger.Create()
        .From("Input1.pdf")
        .From("Input2.pdf")
        .To("Output.pdf", saveOptions)
        .Execute();
                            using Wordize.Merging;

Merger.Create()
        .From("Input1.pdf")
        .From("Input2.pdf")
        .To("Output.pdf", SaveFormat.Pdf)
        .Execute();
            

				    Run code
			    

How to merge multiple PDF files in C#

Connect Wordize SDK to your .NET project
Call the Merge() method, specifying the output file name and collection of input PDF files in parameters
Get the merged PDF file