{"id":16058,"date":"2025-12-11T14:39:16","date_gmt":"2025-12-11T20:39:16","guid":{"rendered":"https:\/\/blog.misumiusa.com\/?page_id=16058"},"modified":"2025-12-11T14:42:57","modified_gmt":"2025-12-11T20:42:57","slug":"bolt-grades-chart","status":"publish","type":"page","link":"https:\/\/us.misumi-ec.com\/blog\/bolt-grades-chart\/","title":{"rendered":"Bolt Grades Chart"},"content":{"rendered":"\n<p>The chart below organizes bolt grades, their head identification marks, and strength values because knowing how to read them helps you choose hardware that&#8217;s right for your job. For example, grade 5 bolt strength is commonly used in general machinery, while grade 8 bolt markings signal a higher tensile rating for heavier-duty assemblies. Metric fasteners follow their own system\u2014bolt strength 10.9 and 12.9 being frequent choices in equipment where shear and tensile demands run higher. Even grade 12 bolts, though less common, appear in specialized high-stress environments.<\/p>\n\n\n\n\n\n\n    <meta charset=\"UTF-8\">\n    <meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0\">\n    <style>\n        .bolt-table-container {\n            font-family: Arial, sans-serif;\n            max-width: 1200px;\n            margin: 0 auto;\n            padding: 20px;\n            background: white;\n        }\n\n        .bolt-table-container h2 {\n            text-align: center;\n            color: #003da5;\n            font-size: 28px;\n            margin-bottom: 30px;\n            font-weight: bold;\n        }\n\n        .bolt-table {\n            width: 100%;\n            border-collapse: separate;\n            border-spacing: 0;\n            box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);\n            background: white;\n        }\n\n        .bolt-table thead {\n            background: #003da5;\n            color: white;\n        }\n\n        .bolt-table th {\n            padding: 15px 10px;\n            text-align: center;\n            font-weight: bold;\n            font-size: 14px;\n            border: 1px solid #ddd;\n        }\n\n        .bolt-table td {\n            padding: 15px 10px;\n            text-align: center;\n            border: 1px solid #ddd;\n            font-size: 13px;\n            vertical-align: middle;\n        }\n\n        .bolt-table tbody tr {\n            background: white;\n            transition: all 0.3s ease;\n        }\n\n        .bolt-table tbody tr:hover {\n            background: #ffdd00;\n            transform: scale(1.02);\n            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);\n            cursor: pointer;\n        }\n\n        .bolt-head-cell {\n            background: #f5f5f5;\n            width: 120px;\n        }\n\n        .bolt-table tbody tr:hover .bolt-head-cell {\n            background: #ffeaa7;\n        }\n\n        .grade-column {\n            text-align: left;\n            padding-left: 15px;\n        }\n\n        .material-desc {\n            font-size: 11px;\n            color: #666;\n            margin-top: 5px;\n        }\n\n        .bolt-svg {\n            width: 80px;\n            height: 80px;\n            margin: 0 auto;\n            display: block;\n        }\n\n        @media (max-width: 768px) {\n            .bolt-table-container {\n                padding: 10px;\n                overflow-x: auto;\n            }\n            \n            .bolt-table {\n                font-size: 11px;\n            }\n            \n            .bolt-svg {\n                width: 60px;\n                height: 60px;\n            }\n        }\n    <\/style>\n\n\n    <div class=\"bolt-table-container\">\n        <h2>US Bolts<\/h2>\n        <table class=\"bolt-table\">\n            <thead>\n                <tr>\n                    <th>Head Marking<\/th>\n                    <th>Grade and Material<\/th>\n                    <th>Nominal Size Range (inches)<\/th>\n                    <th>Proof Load (PSI)<\/th>\n                    <th>Min. Yield Strength (PSI)<\/th>\n                    <th>Min. Tensile Strength (PSI)<\/th>\n                <\/tr>\n            <\/thead>\n            <tbody>\n                <tr>\n                    <td class=\"bolt-head-cell\">\n                        <svg class=\"bolt-svg\" viewBox=\"0 0 100 100\">\n                            <polygon points=\"50,15 85,32.5 85,67.5 50,85 15,67.5 15,32.5\" fill=\"white\" stroke=\"black\" stroke-width=\"2\"><\/polygon>\n                            <text x=\"50\" y=\"55\" text-anchor=\"middle\" font-size=\"20\" font-weight=\"bold\" fill=\"black\">307A<\/text>\n                        <\/svg>\n                    <\/td>\n                    <td class=\"grade-column\">\n                        <strong>307A<\/strong>\n                        <div class=\"material-desc\">Low-carbon steel, standard grade<\/div>\n                    <\/td>\n                    <td>1\/4&#8243; thru 4&#8243;<\/td>\n                    <td>N\/A<\/td>\n                    <td>N\/A<\/td>\n                    <td>60,000<\/td>\n                <\/tr>\n                <tr>\n                    <td class=\"bolt-head-cell\">\n                        <svg class=\"bolt-svg\" viewBox=\"0 0 100 100\">\n                            <polygon points=\"50,15 85,32.5 85,67.5 50,85 15,67.5 15,32.5\" fill=\"white\" stroke=\"black\" stroke-width=\"2\"><\/polygon>\n                        <\/svg>\n                    <\/td>\n                    <td class=\"grade-column\">\n                        <strong>Grade 2<\/strong>\n                        <div class=\"material-desc\">Low to medium-carbon steel, commercial grade<\/div>\n                    <\/td>\n                    <td>1\/4&#8243; thru 3\/4&#8243;<br>Over 3\/4&#8243; thru 1-1\/2&#8243;<\/td>\n                    <td>55,000<br>33,000<\/td>\n                    <td>57,000<br>36,000<\/td>\n                    <td>74,000<br>60,000<\/td>\n                <\/tr>\n                <tr>\n                    <td class=\"bolt-head-cell\">\n                        <svg class=\"bolt-svg\" viewBox=\"0 0 100 100\">\n                            <polygon points=\"50,15 85,32.5 85,67.5 50,85 15,67.5 15,32.5\" fill=\"white\" stroke=\"black\" stroke-width=\"2\"><\/polygon>\n                            <line x1=\"35\" y1=\"35\" x2=\"50\" y2=\"50\" stroke=\"black\" stroke-width=\"3\"><\/line>\n                            <line x1=\"65\" y1=\"35\" x2=\"50\" y2=\"50\" stroke=\"black\" stroke-width=\"3\"><\/line>\n                            <line x1=\"50\" y1=\"50\" x2=\"50\" y2=\"70\" stroke=\"black\" stroke-width=\"3\"><\/line>\n                        <\/svg>\n                    <\/td>\n                    <td class=\"grade-column\">\n                        <strong>Grade 5<\/strong>\n                        <div class=\"material-desc\">Heat-treated medium-carbon steel<\/div>\n                    <\/td>\n                    <td>1\/4&#8243; thru 1&#8243;<br>Over 1&#8243; thru 1-1\/2&#8243;<\/td>\n                    <td>85,000<br>74,000<\/td>\n                    <td>92,000<br>81,000<\/td>\n                    <td>120,000<br>105,000<\/td>\n                <\/tr>\n                <tr>\n                    <td class=\"bolt-head-cell\">\n                        <svg class=\"bolt-svg\" viewBox=\"0 0 100 100\">\n                            <polygon points=\"50,15 85,32.5 85,67.5 50,85 15,67.5 15,32.5\" fill=\"white\" stroke=\"black\" stroke-width=\"2\"><\/polygon>\n                            <line x1=\"50\" y1=\"30\" x2=\"50\" y2=\"70\" stroke=\"black\" stroke-width=\"3\"><\/line>\n                            <line x1=\"30\" y1=\"50\" x2=\"70\" y2=\"50\" stroke=\"black\" stroke-width=\"3\"><\/line>\n                            <line x1=\"35\" y1=\"35\" x2=\"65\" y2=\"65\" stroke=\"black\" stroke-width=\"3\"><\/line>\n                            <line x1=\"65\" y1=\"35\" x2=\"35\" y2=\"65\" stroke=\"black\" stroke-width=\"3\"><\/line>\n                            <line x1=\"38\" y1=\"60\" x2=\"62\" y2=\"40\" stroke=\"black\" stroke-width=\"3\"><\/line>\n                            <line x1=\"38\" y1=\"40\" x2=\"62\" y2=\"60\" stroke=\"black\" stroke-width=\"3\"><\/line>\n                        <\/svg>\n                    <\/td>\n                    <td class=\"grade-column\">\n                        <strong>Grade 8<\/strong>\n                        <div class=\"material-desc\">Heat-treated alloy steel, high strength<\/div>\n                    <\/td>\n                    <td>1\/4&#8243; thru 1-1\/2&#8243;<\/td>\n                    <td>120,000<\/td>\n                    <td>130,000<\/td>\n                    <td>150,000<\/td>\n                <\/tr>\n                <tr>\n                    <td class=\"bolt-head-cell\">\n                        <svg class=\"bolt-svg\" viewBox=\"0 0 100 100\">\n                            <polygon points=\"50,15 85,32.5 85,67.5 50,85 15,67.5 15,32.5\" fill=\"white\" stroke=\"black\" stroke-width=\"2\"><\/polygon>\n                            <text x=\"50\" y=\"55\" text-anchor=\"middle\" font-size=\"18\" font-weight=\"bold\" fill=\"black\">A325<\/text>\n                        <\/svg>\n                    <\/td>\n                    <td class=\"grade-column\">\n                        <strong>Grade A325<\/strong>\n                        <div class=\"material-desc\">Carbon or alloy steel with or without boron<\/div>\n                    <\/td>\n                    <td>1\/2&#8243; thru 1-1\/2&#8243;<\/td>\n                    <td>85,000<\/td>\n                    <td>92,000<\/td>\n                    <td>120,000<\/td>\n                <\/tr>\n                <tr>\n                    <td class=\"bolt-head-cell\">\n                        <svg class=\"bolt-svg\" viewBox=\"0 0 100 100\">\n                            <polygon points=\"50,15 85,32.5 85,67.5 50,85 15,67.5 15,32.5\" fill=\"white\" stroke=\"black\" stroke-width=\"2\"><\/polygon>\n                            <text x=\"50\" y=\"45\" text-anchor=\"middle\" font-size=\"14\" font-weight=\"bold\" fill=\"black\">18-8<\/text>\n                            <text x=\"50\" y=\"62\" text-anchor=\"middle\" font-size=\"14\" font-weight=\"bold\" fill=\"black\">316<\/text>\n                        <\/svg>\n                    <\/td>\n                    <td class=\"grade-column\">\n                        <strong>18-8 &amp; 316 Stainless<\/strong>\n                        <div class=\"material-desc\">Steel alloy with chromium and nickel<\/div>\n                    <\/td>\n                    <td>All sizes thru 1&#8243;<\/td>\n                    <td>N\/A<\/td>\n                    <td>30,000 Min<br>65,000 typical<\/td>\n                    <td>65,000 Min<br>80,000 &#8211; 90,000 typical<\/td>\n                <\/tr>\n                <tr>\n                    <td class=\"bolt-head-cell\">\n                        <svg class=\"bolt-svg\" viewBox=\"0 0 100 100\">\n                            <polygon points=\"50,15 85,32.5 85,67.5 50,85 15,67.5 15,32.5\" fill=\"#cd853f\" stroke=\"black\" stroke-width=\"2\"><\/polygon>\n                            <text x=\"50\" y=\"55\" text-anchor=\"middle\" font-size=\"20\" font-weight=\"bold\" fill=\"black\">651<\/text>\n                        <\/svg>\n                    <\/td>\n                    <td class=\"grade-column\">\n                        <strong>651 Silicon Bronze<\/strong>\n                        <div class=\"material-desc\">Alloy of mostly copper and tin with a small amount of silicon<\/div>\n                    <\/td>\n                    <td>1\/4&#8243; thru 3\/4&#8243;<br>7\/8&#8243; thru 1-1\/2&#8243;<\/td>\n                    <td>N\/A<br>N\/A<\/td>\n                    <td>55,000<br>40,000<\/td>\n                    <td>70,000<br>55,000<\/td>\n                <\/tr>\n                <tr>\n                    <td class=\"bolt-head-cell\">\n                        <svg class=\"bolt-svg\" viewBox=\"0 0 100 100\">\n                            <polygon points=\"50,15 85,32.5 85,67.5 50,85 15,67.5 15,32.5\" fill=\"#c0c0c0\" stroke=\"black\" stroke-width=\"2\"><\/polygon>\n                            <text x=\"50\" y=\"55\" text-anchor=\"middle\" font-size=\"18\" font-weight=\"bold\" fill=\"black\">2024<\/text>\n                        <\/svg>\n                    <\/td>\n                    <td class=\"grade-column\">\n                        <strong>Aluminum 2024<\/strong>\n                        <div class=\"material-desc\">Aluminum alloy with copper, magnesium and manganese; solution heat treated and age hardened<\/div>\n                    <\/td>\n                    <td>All sizes<\/td>\n                    <td>N\/A<\/td>\n                    <td>36,000<\/td>\n                    <td>55,000<\/td>\n                <\/tr>\n            <\/tbody>\n        <\/table>\n    <\/div>\n\n\n\n\n\n\n\n\n    <meta charset=\"UTF-8\">\n    <meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0\">\n    <style>\n        .bolt-table-container {\n            font-family: Arial, sans-serif;\n            max-width: 1200px;\n            margin: 0 auto;\n            padding: 20px;\n            background: white;\n        }\n\n        .bolt-table-container h2 {\n            text-align: center;\n            color: #003da5;\n            font-size: 28px;\n            margin-bottom: 30px;\n            font-weight: bold;\n        }\n\n        .bolt-table {\n            width: 100%;\n            border-collapse: separate;\n            border-spacing: 0;\n            box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);\n            background: white;\n        }\n\n        .bolt-table thead {\n            background: #003da5;\n            color: white;\n        }\n\n        .bolt-table th {\n            padding: 15px 10px;\n            text-align: center;\n            font-weight: bold;\n            font-size: 14px;\n            border: 1px solid #ddd;\n        }\n\n        .bolt-table td {\n            padding: 15px 10px;\n            text-align: center;\n            border: 1px solid #ddd;\n            font-size: 13px;\n            vertical-align: middle;\n        }\n\n        .bolt-table tbody tr {\n            background: white;\n            transition: all 0.3s ease;\n        }\n\n        .bolt-table tbody tr:hover {\n            background: #ffdd00;\n            transform: scale(1.02);\n            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);\n            cursor: pointer;\n        }\n\n        .bolt-head-cell {\n            background: #f5f5f5;\n            width: 120px;\n        }\n\n        .bolt-table tbody tr:hover .bolt-head-cell {\n            background: #ffeaa7;\n        }\n\n        .grade-column {\n            text-align: left;\n            padding-left: 15px;\n        }\n\n        .material-desc {\n            font-size: 11px;\n            color: #666;\n            margin-top: 5px;\n        }\n\n        .bolt-svg {\n            width: 80px;\n            height: 80px;\n            margin: 0 auto;\n            display: block;\n        }\n\n        @media (max-width: 768px) {\n            .bolt-table-container {\n                padding: 10px;\n                overflow-x: auto;\n            }\n            \n            .bolt-table {\n                font-size: 11px;\n            }\n            \n            .bolt-svg {\n                width: 60px;\n                height: 60px;\n            }\n        }\n    <\/style>\n\n\n    <div class=\"bolt-table-container\">\n        <h2>Metric Bolts<\/h2>\n        <table class=\"bolt-table\">\n            <thead>\n                <tr>\n                    <th>Head Marking<\/th>\n                    <th>Class and Material<\/th>\n                    <th>Nominal Size Range (mm)<\/th>\n                    <th>Proof Load (MPa)<\/th>\n                    <th>Min. Yield Strength (MPa)<\/th>\n                    <th>Min. Tensile Strength (MPa)<\/th>\n                <\/tr>\n            <\/thead>\n            <tbody>\n                <tr>\n                    <td class=\"bolt-head-cell\">\n                        <svg class=\"bolt-svg\" viewBox=\"0 0 100 100\">\n                            <polygon points=\"50,15 85,32.5 85,67.5 50,85 15,67.5 15,32.5\" fill=\"white\" stroke=\"black\" stroke-width=\"2\"><\/polygon>\n                            <text x=\"50\" y=\"55\" text-anchor=\"middle\" font-size=\"18\" font-weight=\"bold\" fill=\"black\">8.8<\/text>\n                        <\/svg>\n                    <\/td>\n                    <td class=\"grade-column\">\n                        <strong>Class 8.8<\/strong>\n                        <div class=\"material-desc\">Heat-treated medium-carbon steel<\/div>\n                    <\/td>\n                    <td>All sizes below 16mm<br><br>16mm &#8211; 72mm<\/td>\n                    <td>580<br><br>600<\/td>\n                    <td>640<br><br>660<\/td>\n                    <td>800<br><br>830<\/td>\n                <\/tr>\n                <tr>\n                    <td class=\"bolt-head-cell\">\n                        <svg class=\"bolt-svg\" viewBox=\"0 0 100 100\">\n                            <polygon points=\"50,15 85,32.5 85,67.5 50,85 15,67.5 15,32.5\" fill=\"white\" stroke=\"black\" stroke-width=\"2\"><\/polygon>\n                            <text x=\"50\" y=\"55\" text-anchor=\"middle\" font-size=\"16\" font-weight=\"bold\" fill=\"black\">10.9<\/text>\n                        <\/svg>\n                    <\/td>\n                    <td class=\"grade-column\">\n                        <strong>Class 10.9<\/strong>\n                        <div class=\"material-desc\">Heat-treated alloy steel<\/div>\n                    <\/td>\n                    <td>5mm &#8211; 100mm<\/td>\n                    <td>830<\/td>\n                    <td>940<\/td>\n                    <td>1040<\/td>\n                <\/tr>\n                <tr>\n                    <td class=\"bolt-head-cell\">\n                        <svg class=\"bolt-svg\" viewBox=\"0 0 100 100\">\n                            <polygon points=\"50,15 85,32.5 85,67.5 50,85 15,67.5 15,32.5\" fill=\"white\" stroke=\"black\" stroke-width=\"2\"><\/polygon>\n                            <text x=\"50\" y=\"55\" text-anchor=\"middle\" font-size=\"16\" font-weight=\"bold\" fill=\"black\">12.9<\/text>\n                        <\/svg>\n                    <\/td>\n                    <td class=\"grade-column\">\n                        <strong>Class 12.9<\/strong>\n                        <div class=\"material-desc\">Heat-treated alloy steel, high strength<\/div>\n                    <\/td>\n                    <td>1.6mm &#8211; 100mm<\/td>\n                    <td>970<\/td>\n                    <td>1100<\/td>\n                    <td>1220<\/td>\n                <\/tr>\n                <tr>\n                    <td class=\"bolt-head-cell\">\n                        <svg class=\"bolt-svg\" viewBox=\"0 0 100 100\">\n                            <polygon points=\"50,15 85,32.5 85,67.5 50,85 15,67.5 15,32.5\" fill=\"white\" stroke=\"black\" stroke-width=\"2\"><\/polygon>\n                            <text x=\"50\" y=\"48\" text-anchor=\"middle\" font-size=\"14\" font-weight=\"bold\" fill=\"black\">A-2<\/text>\n                            <text x=\"50\" y=\"65\" text-anchor=\"middle\" font-size=\"14\" font-weight=\"bold\" fill=\"black\">A-4<\/text>\n                        <\/svg>\n                    <\/td>\n                    <td class=\"grade-column\">\n                        <strong>A-2 &amp; A-4 Stainless<\/strong>\n                        <div class=\"material-desc\">Stainless steel with chromium and nickel<\/div>\n                    <\/td>\n                    <td>All sizes thru 20mm<\/td>\n                    <td>N\/A<\/td>\n                    <td>210 Min.<br>450 Typical<\/td>\n                    <td>500 Min.<br>700 Typical<\/td>\n                <\/tr>\n            <\/tbody>\n        <\/table>\n    <\/div>\n\n\n\n\n\n<p><\/p>\n\n\n\n<h2>Parting Thoughts<\/h2>\n\n\n\n<p><a href=\"https:\/\/us.misumi-ec.com\/\">MISUMI USA<\/a>&nbsp;offers a wide range of screws and bolts\u2014both standard and metric\u2014including <a href=\"https:\/\/us.misumi-ec.com\/vona2\/mech_screw\/M3301000000\/M3301090000\/\" title=\"\">hex head bolts<\/a>, narrow head bolts, square head bolts, and more. If you\u2019re unsure which bolt product best suits your application, our engineering team is&nbsp;<a href=\"https:\/\/us.misumi-ec.com\/service\/info\/help-center\/product-support.html\">here to help<\/a>. For more technical insights, explore our other manufacturing-focused tables and articles, such as a <a href=\"https:\/\/us.misumi-ec.com\/blog\/metric-bolt-torque-chart-specs\/\" title=\"\">Metric Bolt Torque Chart<\/a>.<\/p>\n\n\n\n<p>Author:&nbsp;<a href=\"https:\/\/us.misumi-ec.com\/blog\/author\/sbredemann\/\">Scott Bredemann<\/a>&nbsp;| Updated: 12\/11\/2025<\/p>\n\n\n\n<p class=\"has-small-font-size\"><strong>Disclaimer:<br><\/strong>The content on this webpage is for informational purposes only. MISUMI makes no guarantees, expressed or implied, regarding the accuracy, completeness, or validity of the information. Performance parameters, tolerances, designs, materials, or processes should not be assumed to reflect third-party suppliers\u2019 or manufacturers\u2019 deliverables within MISUMI\u2019s network. Buyers are responsible for specifying their part requirements<\/p>\n","protected":false},"excerpt":{"rendered":"<p>The chart below organizes bolt grades, their head identification marks, and strength values because knowing how to read them helps you choose hardware that&#8217;s right for your job. For example, grade 5 bolt strength is commonly used in general machinery, while grade 8 bolt markings signal a higher tensile rating for heavier-duty assemblies. Metric fasteners follow their own system\u2014bolt strength [&hellip;]<\/p>\n","protected":false},"author":70,"featured_media":16067,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"om_disable_all_campaigns":false},"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/us.misumi-ec.com\/blog\/wp-json\/wp\/v2\/pages\/16058"}],"collection":[{"href":"https:\/\/us.misumi-ec.com\/blog\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/us.misumi-ec.com\/blog\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/us.misumi-ec.com\/blog\/wp-json\/wp\/v2\/users\/70"}],"replies":[{"embeddable":true,"href":"https:\/\/us.misumi-ec.com\/blog\/wp-json\/wp\/v2\/comments?post=16058"}],"version-history":[{"count":5,"href":"https:\/\/us.misumi-ec.com\/blog\/wp-json\/wp\/v2\/pages\/16058\/revisions"}],"predecessor-version":[{"id":16068,"href":"https:\/\/us.misumi-ec.com\/blog\/wp-json\/wp\/v2\/pages\/16058\/revisions\/16068"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/us.misumi-ec.com\/blog\/wp-json\/wp\/v2\/media\/16067"}],"wp:attachment":[{"href":"https:\/\/us.misumi-ec.com\/blog\/wp-json\/wp\/v2\/media?parent=16058"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}