Rotativa

var pdf = new ActionAsPdf("ActionName", new { parameters })
{
	FileName = $"{fileName}.pdf",
    CustomSwitches = "--disable-smart-shrinking --load-error-handling ignore",
    PageSize = Size.A4,
    PageMargins = new Margins(0, 0, 0, 0),
};

var pdfByteArr = pdf.BuildFile(this.ControllerContext);

this.Response.AddHeader("Content-Type", "application/pdf");
this.Response.AddHeader("Content-Disposition", "inline");

return this.File(pdfByteArr, "application/pdf");