diff --git a/EssentialCSharp.Web.Tests/SiteMappingTests.cs b/EssentialCSharp.Web.Tests/SiteMappingTests.cs
index 140e982c..a04646bd 100644
--- a/EssentialCSharp.Web.Tests/SiteMappingTests.cs
+++ b/EssentialCSharp.Web.Tests/SiteMappingTests.cs
@@ -78,4 +78,59 @@ public void FindCSyntaxFundamentalsSanitizedWithAnchorReturnsCorrectSiteMap()
         Assert.NotNull(foundSiteMap);
         Assert.Equal(CSyntaxFundamentalsSiteMapping, foundSiteMap);
     }
+
+    [Fact]
+    public void FindPercentComplete_KeyIsNull_ThrowsArgumentNullException()
+    {
+        // Arrange
+
+        // Act
+        string? percent = GetSiteMap().FindPercentComplete(null!);
+
+        // Assert
+        Assert.Null(percent);
+    }
+
+    [Theory]
+    [InlineData("   ")]
+    [InlineData("")]
+    public void FindPercentComplete_KeyIsWhiteSpace_ThrowsArgumentException(string? key)
+    {
+        // Arrange
+
+        // Act
+
+        // Assert
+        Assert.Throws<ArgumentException>(() =>
+        {
+            GetSiteMap().FindPercentComplete(key);
+        });
+    }
+
+    [Theory]
+    [InlineData("hello-world", "50.00")]
+    [InlineData("c-syntax-fundamentals", "100.00")]
+    public void FindPercentComplete_ValidKey_Success(string? key, string result)
+    {
+        // Arrange
+
+        // Act
+        string? percent = GetSiteMap().FindPercentComplete(key);
+
+        // Assert
+        Assert.Equal(result, percent);
+    }
+
+    [Fact]
+    public void FindPercentComplete_EmptySiteMappings_ReturnsZeroPercent()
+    {
+        // Arrange
+        IList<SiteMapping> siteMappings = new List<SiteMapping>();
+
+        // Act
+        string? percent = siteMappings.FindPercentComplete("test");
+
+        // Assert
+        Assert.Equal("0.00", percent);
+    }
 }
diff --git a/EssentialCSharp.Web/Controllers/HomeController.cs b/EssentialCSharp.Web/Controllers/HomeController.cs
index f20f0ee0..690d063a 100644
--- a/EssentialCSharp.Web/Controllers/HomeController.cs
+++ b/EssentialCSharp.Web/Controllers/HomeController.cs
@@ -41,6 +41,7 @@ public IActionResult Index(string key)
 
             ViewBag.PageTitle = siteMapping.IndentLevel is 0 ? siteMapping.ChapterTitle + " " + siteMapping.RawHeading : siteMapping.RawHeading;
             ViewBag.NextPage = FlipPage(siteMapping!.ChapterNumber, siteMapping.PageNumber, true);
+            ViewBag.CurrentPageKey = siteMapping.Key;
             ViewBag.PreviousPage = FlipPage(siteMapping.ChapterNumber, siteMapping.PageNumber, false);
             ViewBag.HeadContents = headHtml;
             ViewBag.Contents = html;
diff --git a/EssentialCSharp.Web/Extensions/SiteMappingListExtensions.cs b/EssentialCSharp.Web/Extensions/SiteMappingListExtensions.cs
index 058e7ff7..c95b4539 100644
--- a/EssentialCSharp.Web/Extensions/SiteMappingListExtensions.cs
+++ b/EssentialCSharp.Web/Extensions/SiteMappingListExtensions.cs
@@ -1,4 +1,7 @@
-namespace EssentialCSharp.Web.Extensions;
+using EssentialCSharp.Common;
+using System.Globalization;
+
+namespace EssentialCSharp.Web.Extensions;
 
 public static class SiteMappingListExtensions
 {
@@ -23,4 +26,50 @@ public static class SiteMappingListExtensions
         }
         return null;
     }
+    /// <summary>
+    /// Finds percent complete based on a key.
+    /// </summary>
+    /// <param name="siteMappings">IList of SiteMappings</param>
+    /// <param name="key">If null, uses the first key in the list</param>
+    /// <returns>Returns a formatted double for use as the percent complete.</returns>
+    public static string? FindPercentComplete(this IList<SiteMapping> siteMappings, string? key)
+    {
+        if (key is null)
+        {
+            return null;
+        }
+        if (key.Trim().Length is 0)
+        {
+            throw new ArgumentException("Parameter key is whitespace or empty: ", nameof(key));
+        }
+        int currentMappingCount = 0;
+        int overallMappingCount = 0;
+        bool currentPageFound = false;
+        IEnumerable<IGrouping<int, SiteMapping>> chapterGroupings = siteMappings.GroupBy(x => x.ChapterNumber).OrderBy(g => g.Key);
+        foreach (IGrouping<int, SiteMapping> chapterGrouping in chapterGroupings)
+        {
+            IEnumerable<IGrouping<int, SiteMapping>> pageGroupings = chapterGrouping.GroupBy(x => x.PageNumber).OrderBy(g => g.Key);
+            foreach (IGrouping<int, SiteMapping> pageGrouping in pageGroupings)
+            {
+                foreach (SiteMapping siteMapping in pageGrouping)
+                {
+                    if (!currentPageFound)
+                    {
+                        currentMappingCount++;
+                    }
+                    overallMappingCount++;
+                    if (siteMapping.Key == key)
+                    {
+                        currentPageFound = true;
+                    }
+                }
+            }
+        }
+        if (overallMappingCount is 0)
+        {
+            return "0.00";
+        }
+        double result = (double)currentMappingCount / overallMappingCount * 100;
+        return string.Format(CultureInfo.InvariantCulture, "{0:0.00}", result);
+    }
 }
diff --git a/EssentialCSharp.Web/Services/SiteMappingService.cs b/EssentialCSharp.Web/Services/SiteMappingService.cs
index c086596f..f95553ba 100644
--- a/EssentialCSharp.Web/Services/SiteMappingService.cs
+++ b/EssentialCSharp.Web/Services/SiteMappingService.cs
@@ -1,4 +1,4 @@
-using EssentialCSharp.Web.Models;
+using System.Globalization;
 
 namespace EssentialCSharp.Web.Services;
 
diff --git a/EssentialCSharp.Web/Views/Shared/_Layout.cshtml b/EssentialCSharp.Web/Views/Shared/_Layout.cshtml
index 04a9367b..0433a4ca 100644
--- a/EssentialCSharp.Web/Views/Shared/_Layout.cshtml
+++ b/EssentialCSharp.Web/Views/Shared/_Layout.cshtml
@@ -120,9 +120,12 @@
                         </div>
                     </div>
 
-                    <a v-if="chapterParentPage" :href="chapterParentPage.href" class="menu-chapter-title text-light">
+                    <a v-if="chapterParentPage" :href="chapterParentPage.href" class="menu menu-chapter-title text-light">
                         <span v-cloak>{{chapterParentPage.title}}</span>
                     </a>
+                    <div class="menu menu-progress text-light" v-if="isContentPage">
+                        <span v-cloak>{{percentComplete}}%</span>
+                    </div>
 
                     <div class="d-flex align-items-center">
                         <div class="border-end pe-3 d-none d-md-block">
@@ -292,8 +295,10 @@
                 Title = $"Chapter {x.Key}: {x.First().ChapterTitle}",
                 Items = GetItems(x, 1)
             });
-        }
 
+            var percentComplete = _SiteMappings.SiteMappings.FindPercentComplete((string) ViewBag.CurrentPageKey);
+        }
+            PERCENT_COMPLETE = @Json.Serialize(percentComplete);
             PREVIOUS_PAGE = @Json.Serialize(ViewBag.PreviousPage)
                 NEXT_PAGE = @Json.Serialize(ViewBag.NextPage)
                     TOC_DATA = @Json.Serialize(tocData)
@@ -343,6 +348,5 @@
         </li>
     </template>
     <script src="~/js/site.js" type="module" asp-append-version="true"></script>
-
 </body>
 </html>
diff --git a/EssentialCSharp.Web/wwwroot/css/styles.css b/EssentialCSharp.Web/wwwroot/css/styles.css
index d39016ad..c476d3da 100644
--- a/EssentialCSharp.Web/wwwroot/css/styles.css
+++ b/EssentialCSharp.Web/wwwroot/css/styles.css
@@ -207,13 +207,16 @@ a:hover {
   }
 }
 
+.menu {
+  white-space: nowrap;
+  overflow: hidden;
+  text-decoration: none;
+}
+
 .menu-brand {
   font-style: normal;
   font-weight: 400;
   font-size: 1.5rem;
-  text-decoration: none;
-  white-space: nowrap;
-  overflow: hidden;
   margin-left: 5px;
 }
 
@@ -221,11 +224,14 @@ a:hover {
   font-style: normal;
   font-weight: 300;
   font-size: 1.2rem;
-  text-decoration: none;
   text-overflow: ellipsis;
-  overflow: hidden;
   cursor: pointer;
-  white-space: nowrap;
+}
+
+.menu-progress {
+  font-style: normal;
+  font-weight: 200;
+  font-size: 1rem;
 }
 
 .has-tooltip {
diff --git a/EssentialCSharp.Web/wwwroot/js/site.js b/EssentialCSharp.Web/wwwroot/js/site.js
index a3e95e07..47477a5c 100644
--- a/EssentialCSharp.Web/wwwroot/js/site.js
+++ b/EssentialCSharp.Web/wwwroot/js/site.js
@@ -194,6 +194,8 @@ const app = createApp({
 
         const currentPage = findCurrentPage([], tocData) ?? [];
 
+        const percentComplete = ref(PERCENT_COMPLETE);
+
         const chapterParentPage = currentPage.find((parent) => parent.level === 0);
 
         const sectionTitle = ref(currentPage?.[0]?.title || "Essential C#");
@@ -255,6 +257,11 @@ const app = createApp({
             return tocData.filter(item => filterItem(item, query));
         });
 
+        const isContentPage = computed(() => {
+            let path = window.location.pathname;
+            return path !== '/home' && path !== '/guidelines' && path !== '/about' && path !== '/announcements';
+        });
+
         function filterItem(item, query) {
             let matches = normalizeString(item.title).includes(query);
             if (item.items && item.items.length) {
@@ -311,11 +318,13 @@ const app = createApp({
             tocData,
             expandedTocs,
             currentPage,
+            percentComplete,
             chapterParentPage,
 
             searchQuery,
             filteredTocData,
-            enableTocFilter
+            enableTocFilter,
+            isContentPage
         };
     },
 });