SelectPdf vs IronPDF. An IronPDF alternative for .NET.

IronPDF and SelectPdf at a glance.

IronPDF is a commercial .NET PDF library from Iron Software. SelectPdf.Universal is the cross-platform .NET PDF library from SelectPdf. Both convert URLs and HTML strings to PDF with a Chromium-based engine, so modern CSS, web fonts and JavaScript render in both, and both create, edit and read PDF documents: merge and split, watermarks and stamps, form filling, text extraction, PDF to image, digital signatures and PDF/A.

Comparisons written before October 2026 describe SelectPdf as a Windows-only library with WebKit and Blink engines. That was the classic SelectPdf library. Since version 26.4, SelectPdf.Universal runs on Windows, Linux, macOS and in Docker with Chromium, and version 26.5 added a remote engine for Alpine Linux and Kubernetes. The classic library is still maintained for Windows, and one license covers both.

Moving from one to the other is mostly renaming types and converting units: SelectPdf margins are in points where IronPDF's are in millimetres, and the page-number placeholders change. The sections below show where SelectPdf comes out ahead, how to migrate IronPDF code to SelectPdf, and what each license costs.

Where SelectPdf is ahead.

Prices from each vendor's pricing page. Measurements from the 2026-10-15 run of the open pdf-benchmarks harness: IronPDF 2026.10.3 and SelectPdf.Universal 26.5.0 on the same machine.

Every number above, with the rest of the measurements, is in the full table below.

Migrate IronPDF code to SelectPdf.

The same document in both libraries: an HTML page with a centred header and a "Page N of M" footer. Install the library and the engine package for your platform:

dotnet add package SelectPdf.Universal
dotnet add package SelectPdf.Universal.Native.win-x64

IronPDF:

using IronPdf;

License.LicenseKey = "...";

ChromePdfRenderer renderer = new ChromePdfRenderer();
renderer.RenderingOptions.TextHeader = new TextHeaderFooter
{
    CenterText = "Quarterly report",
};
renderer.RenderingOptions.TextFooter = new TextHeaderFooter
{
    CenterText = "Page {page} of {total-pages}",
};

PdfDocument pdf = renderer.RenderHtmlAsPdf(html);
pdf.SaveAs("report.pdf");

SelectPdf:

using SelectPdf.Universal;

HtmlToPdf converter = new HtmlToPdf();

converter.Options.DisplayHeader = true;
converter.Header.Height = 40;
PdfTextSection header = new PdfTextSection(0, 15, "Quarterly report",
    PdfFont.CreateStandardFont(PdfStandardFont.Helvetica, 10));
header.HorizontalAlign = PdfTextHorizontalAlign.Center;
converter.Header.Add(header);

converter.Options.DisplayFooter = true;
converter.Footer.Height = 40;
PdfTextSection footer = new PdfTextSection(0, 10, "Page {page_number} of {total_pages}",
    PdfFont.CreateStandardFont(PdfStandardFont.Helvetica, 10));
footer.HorizontalAlign = PdfTextHorizontalAlign.Center;
converter.Footer.Add(footer);

PdfDocument doc = converter.ConvertHtmlString(html);
doc.Save("report.pdf");
doc.Close();

Thirteen tasks side by side, from hello world to merge, watermarks, forms, text extraction, images, signatures, PDF/A and an ASP.NET Core endpoint, each built and checked, are in the migration guide on GitHub.

Map IronPDF APIs to SelectPdf.

SelectPdf margins are in points (1 mm is about 2.83 pt) and delays in seconds.

The complete mapping, with every option, is in the migration guide; every class is in the documentation.

IronPDF and SelectPdf pricing.

Both sell perpetual licenses with one year of updates. Each situation is priced with the cheapest published license that covers it; prices read on 2026-10-22.

From ironpdf.com/licensing and SelectPdf pricing. After the first year, renewing updates and support is optional with both: IronPDF's renewal is USD 599 a year for Lite. Iron Software has announced higher Professional and Unlimited prices from November 1, 2026; check both pages for current terms before buying. One SelectPdf license covers SelectPdf.Universal and the classic Windows library.

The full measurement.

IronPDF 2026.10.3 and SelectPdf.Universal 26.5.0 on every axis of the 2026-10-15 run, on one machine under Windows and Linux, generated from the raw data. The method, per-page numbers and eight other .NET PDF libraries are on the results page; the harness is open source, so every number can be re-run.

Linux, Docker and ARM64.

The engine package bundles the Chromium libraries, so a Docker image built from the official .NET images needs no apt-get lines and no installation settings, and it runs as root or as a non-root user. Linux x64 and ARM64 each have their own package; Linux needs glibc 2.30 or later (Debian 11+, Ubuntu 20.04+, RHEL 9+). On Alpine, the conversions run in the SelectPdf engine container instead.

Step by step: HTML to PDF in Docker on Linux. Both libraries' Dockerfiles are side by side in the C# PDF libraries comparison.