{"id":9758,"date":"2026-10-31T11:25:36","date_gmt":"2026-10-31T11:25:36","guid":{"rendered":"https:\/\/cerapuresteel.com\/stainless-steel-pipe-sizes-chart\/"},"modified":"2026-10-31T11:25:36","modified_gmt":"2026-10-31T11:25:36","slug":"stainless-steel-pipe-sizes-chart","status":"publish","type":"post","link":"https:\/\/cerapuresteel.com\/stainless-steel-pipe-sizes-chart\/","title":{"rendered":"Stainless Steel Pipe Sizes Chart: Dimensions in MM and Inches"},"content":{"rendered":"<style>.cps-table td,.cps-table th{border:1px solid #ddd;padding:8px}<\/style>\n<p>A stainless steel pipe sizes chart helps engineers, contractors, fabricators and purchasing teams identify the correct pipe dimensions for an industrial project. Pipe sizing involves more than selecting a diameter. Outside diameter, nominal pipe size, wall thickness, schedule, material grade and applicable manufacturing standard must all be considered.<\/p>\n<p>Stainless steel pipes are used in food processing, pharmaceutical equipment, chemical plants, water treatment, manufacturing and industrial utility systems. The correct size supports dimensional compatibility, flow calculations, installation and procurement.<\/p>\n<p>This guide explains stainless steel pipe dimensions, NPS, nominal bore, schedule numbers and the difference between pipe and tube sizing.<\/p>\n<h2>Understanding Stainless Steel Pipe Dimensions<\/h2>\n<p><strong>Nominal Pipe Size (NPS):<\/strong> A standardized nominal designation used for many piping systems.<\/p>\n<p><strong>Outside Diameter (OD):<\/strong> The actual external diameter of the pipe.<\/p>\n<p><strong>Wall Thickness:<\/strong> The thickness of the pipe wall.<\/p>\n<p><strong>Schedule:<\/strong> A designation associated with standardized pipe wall thicknesses for a given nominal size.<\/p>\n<p>A nominal pipe size does not necessarily equal the actual outside diameter in inches. For example, NPS 1 pipe has a standardized outside diameter of approximately 33.4 mm.<\/p>\n<h2>Stainless Steel Pipe Size Chart<\/h2>\n<p>The following reference table lists common NPS sizes and their standardized outside diameters. It is not a complete dimensional specification; wall thickness must be selected separately.<\/p>\n<table class=\"cps-table\" style=\"width:100%;border-collapse:collapse\">\n<thead>\n<tr>\n<th><strong>Nominal Pipe Size (NPS)<\/strong><\/th>\n<th><strong>Approx. OD (mm)<\/strong><\/th>\n<th><strong>OD (inches)<\/strong><\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>1\/8<\/td>\n<td>10.3<\/td>\n<td>0.405<\/td>\n<\/tr>\n<tr>\n<td>1\/4<\/td>\n<td>13.7<\/td>\n<td>0.540<\/td>\n<\/tr>\n<tr>\n<td>3\/8<\/td>\n<td>17.1<\/td>\n<td>0.675<\/td>\n<\/tr>\n<tr>\n<td>1\/2<\/td>\n<td>21.3<\/td>\n<td>0.840<\/td>\n<\/tr>\n<tr>\n<td>3\/4<\/td>\n<td>26.7<\/td>\n<td>1.050<\/td>\n<\/tr>\n<tr>\n<td>1<\/td>\n<td>33.4<\/td>\n<td>1.315<\/td>\n<\/tr>\n<tr>\n<td>1 1\/4<\/td>\n<td>42.2<\/td>\n<td>1.660<\/td>\n<\/tr>\n<tr>\n<td>1 1\/2<\/td>\n<td>48.3<\/td>\n<td>1.900<\/td>\n<\/tr>\n<tr>\n<td>2<\/td>\n<td>60.3<\/td>\n<td>2.375<\/td>\n<\/tr>\n<tr>\n<td>2 1\/2<\/td>\n<td>73.0<\/td>\n<td>2.875<\/td>\n<\/tr>\n<tr>\n<td>3<\/td>\n<td>88.9<\/td>\n<td>3.500<\/td>\n<\/tr>\n<tr>\n<td>4<\/td>\n<td>114.3<\/td>\n<td>4.500<\/td>\n<\/tr>\n<tr>\n<td>5<\/td>\n<td>141.3<\/td>\n<td>5.563<\/td>\n<\/tr>\n<tr>\n<td>6<\/td>\n<td>168.3<\/td>\n<td>6.625<\/td>\n<\/tr>\n<tr>\n<td>8<\/td>\n<td>219.1<\/td>\n<td>8.625<\/td>\n<\/tr>\n<tr>\n<td>10<\/td>\n<td>273.1<\/td>\n<td>10.750<\/td>\n<\/tr>\n<tr>\n<td>12<\/td>\n<td>323.9<\/td>\n<td>12.750<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Dimensions are nominal reference values based on common NPS pipe dimensions. Verify the governing dimensional standard, tolerance and product specification before ordering.<\/p>\n<h2>Stainless Steel Pipe Schedule Chart Explained<\/h2>\n<p>Pipe schedules identify standardized wall thickness series for each nominal pipe size. Common schedules include 5S, 10S, 40, 40S and 80S, depending on the product and applicable standard.<\/p>\n<table class=\"cps-table\" style=\"width:100%;border-collapse:collapse\">\n<thead>\n<tr>\n<th><strong>Schedule<\/strong><\/th>\n<th><strong>What It Indicates<\/strong><\/th>\n<th><strong>Important Note<\/strong><\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Schedule 5S<\/td>\n<td>A thin-wall stainless steel pipe series where specified<\/td>\n<td>Availability depends on size and product standard<\/td>\n<\/tr>\n<tr>\n<td>Schedule 10S<\/td>\n<td>A commonly used stainless steel schedule series<\/td>\n<td>Exact thickness varies by NPS<\/td>\n<\/tr>\n<tr>\n<td>Schedule 40<\/td>\n<td>A standardized wall thickness series<\/td>\n<td>Not the same thickness for every pipe diameter<\/td>\n<\/tr>\n<tr>\n<td>Schedule 40S<\/td>\n<td>A stainless steel schedule designation<\/td>\n<td>Check the applicable dimensional table<\/td>\n<\/tr>\n<tr>\n<td>Schedule 80<\/td>\n<td>A thicker-wall series for many sizes<\/td>\n<td>Actual dimensions must be confirmed<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>A schedule number does not directly state wall thickness in millimetres. Always check the dimensional table for the selected NPS and schedule.<\/p>\n<h2>How to Calculate Inside Diameter<\/h2>\n<p>Inside diameter can be calculated using: ID = OD \u2212 (2 \u00d7 wall thickness).<\/p>\n<p>For example, assume a pipe has an outside diameter of 33.4 mm and a wall thickness of 3.38 mm. Inside diameter = 33.4 \u2212 (2 \u00d7 3.38) = approximately 26.64 mm. This is a geometric calculation based on the assumed dimensions; actual internal dimensions can vary within manufacturing tolerances.<\/p>\n<h2>Pipe vs Tube: What Is the Difference?<\/h2>\n<table class=\"cps-table\" style=\"width:100%;border-collapse:collapse\">\n<thead>\n<tr>\n<th><strong>Feature<\/strong><\/th>\n<th><strong>Pipe<\/strong><\/th>\n<th><strong>Tube<\/strong><\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Typical sizing<\/td>\n<td>Nominal pipe size and schedule, or specified dimensions<\/td>\n<td>Actual OD and wall thickness commonly specified<\/td>\n<\/tr>\n<tr>\n<td>Common use<\/td>\n<td>Piping systems and fluid transportation<\/td>\n<td>Precision equipment, process systems and specialized fabrication<\/td>\n<\/tr>\n<tr>\n<td>Dimension selection<\/td>\n<td>NPS, OD, schedule and applicable standard<\/td>\n<td>OD, wall thickness, tolerance and applicable standard<\/td>\n<\/tr>\n<tr>\n<td>Key requirement<\/td>\n<td>Service conditions and piping design<\/td>\n<td>Dimensional accuracy and application-specific performance<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>For pharmaceutical and high-purity systems, tubing may require additional specifications for internal surface finish, cleanliness, weld condition and hygienic performance.<\/p>\n<h2>How to Select the Correct Stainless Steel Pipe Size<\/h2>\n<ol>\n<li>Determine the required flow rate, fluid properties, pressure drop and system layout.<\/li>\n<li>Confirm design pressure, temperature, corrosion conditions and applicable engineering codes.<\/li>\n<li>Select the material grade according to the operating environment.<\/li>\n<li>Confirm the required pipe schedule or actual wall thickness against the relevant standard.<\/li>\n<li>Check compatibility with fittings, valves, flanges and connection methods.<\/li>\n<li>Verify that the selected product standard matches the intended pipe or tube application.<\/li>\n<\/ol>\n<h2>Common Stainless Steel Pipe Sizing Mistakes<\/h2>\n<ul>\n<li>Assuming nominal pipe size equals actual outside diameter.<\/li>\n<li>Selecting a schedule without checking wall thickness.<\/li>\n<li>Confusing pipe dimensions with tube dimensions.<\/li>\n<li>Ignoring dimensional tolerances.<\/li>\n<li>Choosing a size without evaluating flow and design pressure.<\/li>\n<li>Using general industrial pipe where certified sanitary tubing is required.<\/li>\n<\/ul>\n<h2>Frequently Asked Questions<\/h2>\n<h3>What is the standard size of a stainless steel pipe?<\/h3>\n<p>There is no single standard size. Pipes are available in multiple nominal sizes, outside diameters and wall thicknesses according to the applicable product standard.<\/p>\n<h3>What is the OD of a 1-inch stainless steel pipe?<\/h3>\n<p>For common NPS piping, NPS 1 has a standardized outside diameter of approximately 33.4 mm or 1.315 inches.<\/p>\n<h3>What is the difference between NPS and OD?<\/h3>\n<p>NPS is a nominal size designation, whereas OD is the actual specified outside diameter. They are not always numerically equal.<\/p>\n<h3>What does Schedule 40 mean?<\/h3>\n<p>Schedule 40 is a standardized wall thickness series. Its exact thickness depends on nominal pipe size.<\/p>\n<h3>Where can I check stainless steel pipe weight?<\/h3>\n<p>Use a dimension-specific <a href=\"https:\/\/cerapuresteel.com\/ss-pipe-weight-chart-stainless-steel-pipe-weight-chart\/\">weight chart<\/a> or Cera Pure Steel&#8217;s <a href=\"https:\/\/cerapuresteel.com\/pipe-weight-calculator\/\">pipe weight calculator<\/a> with the correct outside diameter and wall thickness.<\/p>\n<h2>Conclusion<\/h2>\n<p>A stainless steel pipe sizes chart simplifies selection by connecting nominal size, outside diameter and wall thickness. Verify the applicable standard, material grade, dimensions, tolerances and service requirements before ordering.<\/p>\n<h2>Related Guides<\/h2>\n<ul>\n<li><a href=\"https:\/\/cerapuresteel.com\/stainless-steel-erw-pipe\/\">Stainless Steel ERW Pipe Guide<\/a><\/li>\n<li><a href=\"https:\/\/cerapuresteel.com\/ss-304-pipe-weight-calculator\/\">SS 304 Pipe Weight Calculator Guide<\/a><\/li>\n<li><a href=\"https:\/\/cerapuresteel.com\/stainless-steel-pipe-price-list\/\">Stainless Steel Pipe Price List<\/a><\/li>\n<li><a href=\"https:\/\/cerapuresteel.com\/erw-pipe-full-form\/\">ERW Pipe Full Form<\/a><\/li>\n<li><a href=\"https:\/\/cerapuresteel.com\/stainless-steel-tubes-grades-sizes-applications\/\">Stainless Steel Tubes Guide<\/a><\/li>\n<li><a href=\"https:\/\/cerapuresteel.com\/stainless-steel-seamless-pipes-tubes-guide\/\">Seamless Pipes and Tubes Guide<\/a><\/li>\n<li><a href=\"https:\/\/cerapuresteel.com\/pipe-weight-calculator\/\">Online Pipe Weight Calculator<\/a><\/li>\n<li><a href=\"https:\/\/cerapuresteel.com\/welded-stainless-steel-tubes\/\">Welded Stainless Steel Tubes<\/a><\/li>\n<\/ul>\n<p><strong>Need a quotation?<\/strong> Share your grade, size, quantity and standard with our team via the <a href=\"https:\/\/cerapuresteel.com\/contact-us\/\">Cera Pure Steel contact page<\/a> or call <a href=\"tel:+918793847434\">+91 87938 47434<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Check the stainless steel pipe sizes chart in mm and inches. Understand pipe OD, NPS, schedule, wall thickness and SS pipe dimensions.<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_thinkrank_schema_form_data":"","_thinkrank_selected_schema_type":"","_thinkrank_additional_schemas":"","_thinkrank_canonical_url":"","_thinkrank_og_title":"Stainless Steel Pipe Sizes Chart in MM and Inches","_thinkrank_og_description":"Check the stainless steel pipe sizes chart in mm and inches. 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