How to Convert Microsoft Word to PDF in C#

What Does the Original Document Look Like?

How Do I Write the C# Code?

Additionally, the RenderDocxAsPdf method also accepts DOCX data as bytes and streams. This flexibility allows you to work with documents from various sources, whether they're stored on disk, in memory, or retrieved from a database. The method handles all the complex conversion logic internally, ensuring that fonts, images, tables, and formatting are accurately preserved.

:path=/static-assets/pdf/content-code-examples/how-to/docx-to-pdf-from-file.cs
using IronPdf;

// Instantiate Renderer
DocxToPdfRenderer renderer = new DocxToPdfRenderer();

// Render from DOCX file
PdfDocument pdf = renderer.RenderDocxAsPdf("Modern-chronological-resume.docx");

// Save the PDF
pdf.SaveAs("pdfFromDocx.pdf");

using IronPdf;

// Instantiate Renderer
DocxToPdfRenderer renderer = new DocxToPdfRenderer();

// Render from DOCX file
PdfDocument pdf = renderer.RenderDocxAsPdf("Modern-chronological-resume.docx");

// Save the PDF
pdf.SaveAs("pdfFromDocx.pdf");
using IronPdf;

// Instantiate Renderer
DocxToPdfRenderer renderer = new DocxToPdfRenderer();

// Render from DOCX file
PdfDocument pdf = renderer.RenderDocxAsPdf("Modern-chronological-resume.docx");

// Save the PDF
pdf.SaveAs("pdfFromDocx.pdf");

For more advanced scenarios, you can also convert from byte arrays or streams:

// Convert from byte array
byte[] docxBytes = File.ReadAllBytes("document.docx");
PdfDocument pdfFromBytes = renderer.RenderDocxAsPdf(docxBytes);

// Convert from stream
using (FileStream stream = new FileStream("document.docx", FileMode.Open))
{
    PdfDocument pdfFromStream = renderer.RenderDocxAsPdf(stream);
}

// Convert from byte array
byte[] docxBytes = File.ReadAllBytes("document.docx");
PdfDocument pdfFromBytes = renderer.RenderDocxAsPdf(docxBytes);

// Convert from stream
using (FileStream stream = new FileStream("document.docx", FileMode.Open))
{
    PdfDocument pdfFromStream = renderer.RenderDocxAsPdf(stream);
}

What Will the Converted PDF Look Like?

The resulting PDF maintains all the original formatting, including fonts, colors, layout, and embedded images. This makes IronPDF ideal for generating professional documents that need to be shared or archived in a universally accessible format.

What Data Model Should I Create?

First, let's create a model to store the information that will be mail-merged into its corresponding placeholder. The property names in your data model must match the merge field names in your Word template exactly (case-sensitive).

:path=/static-assets/pdf/content-code-examples/how-to/docx-to-pdf-mail-merge-model.cs
internal class RecipientsDataModel
{
    public string Date { get; set; }
    public string Location{ get; set; }
    public string Recipients_Name { get; set; }
    public string Contact_Us { get; set; }
}

internal class RecipientsDataModel
{
    public string Date { get; set; }
    public string Location{ get; set; }
    public string Recipients_Name { get; set; }
    public string Contact_Us { get; set; }
}
internal class RecipientsDataModel
{
    public string Date { get; set; }
    public string Location{ get; set; }
    public string Recipients_Name { get; set; }
    public string Contact_Us { get; set; }
}

I have modified a template provided by Microsoft Word for our purposes. Please download the Party Invitation DOTX example file. For our use case, let's set the MailMergePrintAllInOnePdfDocument property to true, which combines the PDFs into a single PdfDocument object. The merge fields that we are going to use are Date, Location, Recipient's Name, and Contact Us.

What Does the Mail Merge Template Look Like?

How Do I Implement the Mail Merge Code?

The Mail Merge functionality in IronPDF supports various rendering options that can be configured through the DocxPdfRenderOptions class. This allows you to control aspects like page orientation, margins, and whether to combine all merged documents into a single PDF or generate separate files.

:path=/static-assets/pdf/content-code-examples/how-to/docx-to-pdf-mail-merge.cs
using IronPdf;
using System.Collections.Generic;
using System.Linq;

var recipients = new List<RecipientsDataModel>()
    {
        new RecipientsDataModel()
        {
            Date ="Saturday, October 15th, 2023",
            Location="Iron Software Cafe, Chiang Mai",
            Recipients_Name="Olivia Smith",
            Contact_Us = "support@ironsoftware.com"
        },
        new RecipientsDataModel()
        {
            Date ="Saturday, October 15th, 2023",
            Location="Iron Software Cafe, Chiang Mai",
            Recipients_Name="Ethan Davis",
            Contact_Us = "support@ironsoftware.com"
        },
    };

DocxToPdfRenderer docxToPdfRenderer = new DocxToPdfRenderer();

// Apply render options
DocxPdfRenderOptions options = new DocxPdfRenderOptions();

// Configure the output PDF to be combined into a single PDF document
options.MailMergePrintAllInOnePdfDocument = true;

// Convert DOTX to PDF
var pdfs = docxToPdfRenderer.RenderDocxMailMergeAsPdf<RecipientsDataModel>(
     recipients,
     "Party-invitation.dotx",
     options);

pdfs.First().SaveAs("mailMerge.pdf");

using IronPdf;
using System.Collections.Generic;
using System.Linq;

var recipients = new List<RecipientsDataModel>()
    {
        new RecipientsDataModel()
        {
            Date ="Saturday, October 15th, 2023",
            Location="Iron Software Cafe, Chiang Mai",
            Recipients_Name="Olivia Smith",
            Contact_Us = "support@ironsoftware.com"
        },
        new RecipientsDataModel()
        {
            Date ="Saturday, October 15th, 2023",
            Location="Iron Software Cafe, Chiang Mai",
            Recipients_Name="Ethan Davis",
            Contact_Us = "support@ironsoftware.com"
        },
    };

DocxToPdfRenderer docxToPdfRenderer = new DocxToPdfRenderer();

// Apply render options
DocxPdfRenderOptions options = new DocxPdfRenderOptions();

// Configure the output PDF to be combined into a single PDF document
options.MailMergePrintAllInOnePdfDocument = true;

// Convert DOTX to PDF
var pdfs = docxToPdfRenderer.RenderDocxMailMergeAsPdf<RecipientsDataModel>(
     recipients,
     "Party-invitation.dotx",
     options);

pdfs.First().SaveAs("mailMerge.pdf");
using IronPdf;
using System.Collections.Generic;
using System.Linq;

var recipients = new List<RecipientsDataModel>()
    {
        new RecipientsDataModel()
        {
            Date ="Saturday, October 15th, 2023",
            Location="Iron Software Cafe, Chiang Mai",
            Recipients_Name="Olivia Smith",
            Contact_Us = "support@ironsoftware.com"
        },
        new RecipientsDataModel()
        {
            Date ="Saturday, October 15th, 2023",
            Location="Iron Software Cafe, Chiang Mai",
            Recipients_Name="Ethan Davis",
            Contact_Us = "support@ironsoftware.com"
        },
    };

DocxToPdfRenderer docxToPdfRenderer = new DocxToPdfRenderer();

// Apply render options
DocxPdfRenderOptions options = new DocxPdfRenderOptions();

// Configure the output PDF to be combined into a single PDF document
options.MailMergePrintAllInOnePdfDocument = true;

// Convert DOTX to PDF
var pdfs = docxToPdfRenderer.RenderDocxMailMergeAsPdf<RecipientsDataModel>(
     recipients,
     "Party-invitation.dotx",
     options);

pdfs.First().SaveAs("mailMerge.pdf");

What Does the Final Merged PDF Look Like?

Once the PDF document is created, you have the flexibility to make additional changes. These include exporting it as PDF/A or PDF/UA for archival and accessibility compliance, as well as adding a digital certificate for document authentication. You can also manipulate individual pages by merging or splitting PDFs, rotating pages, and you have the option to apply annotations and bookmarks for better document navigation.

Aside from those features, IronPDF also supports converting to other document formats. For example, you can convert Markdown to PDF, convert RTF to PDF, or even export PDFs back to HTML. For additional information regarding the other functionality that IronPDF has to offer, please refer to the comprehensive HTML to PDF tutorial.