diff --git a/ShopOnline.Api/Controllers/ShoppingCartController.cs b/ShopOnline.Api/Controllers/ShoppingCartController.cs
index 7fd9377..8dd5b48 100644
--- a/ShopOnline.Api/Controllers/ShoppingCartController.cs
+++ b/ShopOnline.Api/Controllers/ShoppingCartController.cs
@@ -128,5 +128,29 @@ namespace ShopOnline.Api.Controllers
 
             }
         }
+
+        [HttpPatch("{id:int}")]
+        public async Task<ActionResult<CartItemDto>> UpdateQuantity(int id, CartItemQuantityUpdateDto cartItemQuantityUpdateDto)
+        {
+            try
+            {
+                var cartItem = await this.shoppingCartRepository.UpdateQuantity(id, cartItemQuantityUpdateDto);
+                if(cartItem == null)
+                {
+                    return NotFound();
+                }
+
+                var product = await productRepository.GetItem(cartItem.ProductId);
+
+                var cartItemDto = cartItem.ConvertToDto(product);
+
+                return Ok(cartItemDto);
+            }
+            catch (Exception ex)
+            {
+                return StatusCode(StatusCodes.Status500InternalServerError, ex.Message);
+
+            }
+        }
     }
 }
diff --git a/ShopOnline.Api/Repositories/ShoppingCartRepository.cs b/ShopOnline.Api/Repositories/ShoppingCartRepository.cs
index 76b2154..d2d7c3f 100644
--- a/ShopOnline.Api/Repositories/ShoppingCartRepository.cs
+++ b/ShopOnline.Api/Repositories/ShoppingCartRepository.cs
@@ -87,9 +87,18 @@ namespace ShopOnline.Api.Repositories
                           }).ToListAsync();
         }
 
-        public Task<CartItem> UpdateQuantity(int id, CartItemQuantityUpdateDto cartItemQuantityUpdateDto)
+        public async Task<CartItem> UpdateQuantity(int id, CartItemQuantityUpdateDto cartItemQuantityUpdateDto)
         {
-            throw new NotImplementedException();
+            var item = await this.shopOnlineDbContext.CartItems.FindAsync(id);
+
+            if(item != null)
+            {
+                item.Quantity = cartItemQuantityUpdateDto.Quantity;
+                await this.shopOnlineDbContext.SaveChangesAsync();
+                return item;
+            }
+
+            return null;
         }
     }
 }
diff --git a/ShopOnline.Web/Pages/ShoppingCart.razor b/ShopOnline.Web/Pages/ShoppingCart.razor
index 208d6f9..86c70ac 100644
--- a/ShopOnline.Web/Pages/ShoppingCart.razor
+++ b/ShopOnline.Web/Pages/ShoppingCart.razor
@@ -19,7 +19,12 @@ else {
                     <div class="col-md-8">
                         <h5>@item.ProductName</h5>
                         <div class="mb-4">@item.ProductDescription</div>
-                        <span>Price: <b>@item.Price.ToString("C")</b></span>
+                        <span>Price: <b>@item.Price.ToString("C")</b>
+                            <input type="number" @bind="@item.Quantity"/>
+                            <button class="btn btn-info btn-sm"
+                                @onclick="(()=> UpdateQuantityCartItem_Click(item.Id, item.Quantity))"
+                            >Update Quantity</button>
+                        </span>
                         <div>
                             <button @onclick = "(() => DeleteCartItem_Click(item.Id))"
                                 class="btn btn-danger sm">Remove</button>
@@ -31,7 +36,7 @@ else {
         <div class="col-md-3">
             <h5>Cart Summary</h5>
             <div class="mt-2">
-                <div>Total - </div>
+                <div>Total - (@TotalQuantity items)&nbsp; <b>@TotalPrice</b></div>
                 <a href="#" class="btn btn-success">
                     <span class="oi oi-credit-card"></span>&nbsp; Proceed to Checkout
                 </a>
diff --git a/ShopOnline.Web/Pages/ShoppingCartBase.cs b/ShopOnline.Web/Pages/ShoppingCartBase.cs
index 011d148..e6cd164 100644
--- a/ShopOnline.Web/Pages/ShoppingCartBase.cs
+++ b/ShopOnline.Web/Pages/ShoppingCartBase.cs
@@ -13,11 +13,15 @@ namespace ShopOnline.Web.Pages
 
         public string ErrorMessage { get; set; }
 
+        protected string TotalPrice { get; set; }
+        protected int TotalQuantity { get; set; }
+
         protected override async Task OnInitializedAsync()
         {
             try
             {
                 ShoppingCartItems = await ShoppingCartService.GetItems(HardCoded.UserId);
+                CalculateCartSummaryTotals();
             }
             catch (Exception ex)
             {
@@ -30,9 +34,71 @@ namespace ShopOnline.Web.Pages
             var cartItemDto = await ShoppingCartService.DeleteItem(id);
 
             RemoveCartItem(id);
+            CalculateCartSummaryTotals();
 
         }
 
+        protected async Task UpdateQuantityCartItem_Click(int id, int quantity)
+        {
+            try
+            {
+                if(quantity > 0)
+                {
+                    var updateItemDto = new CartItemQuantityUpdateDto
+                    {
+                        CartItemId = id,
+                        Quantity = quantity
+                    };
+
+                    var returnedUpdateItemDto = await this.ShoppingCartService.UpdateQuantity(updateItemDto);
+
+                    UpdateItemTotalPrice(returnedUpdateItemDto);
+                    CalculateCartSummaryTotals();
+                }
+                else
+                {
+                    var item = this.ShoppingCartItems.FirstOrDefault(i => i.Id == id);
+                    
+                    if(item != null)
+                    {
+                        item.Quantity = 1;
+                        item.TotalPrice = item.Price;
+                    }
+                }
+            }
+            catch (Exception)
+            {
+
+                throw;
+            }
+        }
+
+        private void UpdateItemTotalPrice(CartItemDto cartItemDto)
+        {
+            var item = GetCartItem(cartItemDto.Id);
+            
+            if(item != null)
+            {
+                item.TotalPrice = cartItemDto.Price * cartItemDto.Quantity;
+            }
+        }
+
+        private void CalculateCartSummaryTotals()
+        {
+            SetTotalPrice();
+            SetTotalQuantity();
+        }
+
+        private void SetTotalPrice()
+        {
+            TotalPrice = this.ShoppingCartItems.Sum(p => p.TotalPrice).ToString("C");
+        }
+
+        private void SetTotalQuantity()
+        {
+            TotalQuantity = this.ShoppingCartItems.Sum(p => p.Quantity);
+        }
+
         private CartItemDto GetCartItem(int id)
         {
             return ShoppingCartItems.FirstOrDefault(i => i.Id == id);
@@ -44,5 +110,7 @@ namespace ShopOnline.Web.Pages
 
             ShoppingCartItems.Remove(CartItemDto);
         }
+
+
     }
 }
diff --git a/ShopOnline.Web/Services/Contracts/IShoppingCartService.cs b/ShopOnline.Web/Services/Contracts/IShoppingCartService.cs
index 4d974a5..0a9fbaa 100644
--- a/ShopOnline.Web/Services/Contracts/IShoppingCartService.cs
+++ b/ShopOnline.Web/Services/Contracts/IShoppingCartService.cs
@@ -7,5 +7,6 @@ namespace ShopOnline.Web.Services.Contracts
         Task<List<CartItemDto>> GetItems(int userId);
         Task<CartItemDto> AddItem(CartItemToAddDto cartItemToAddDto);
         Task<CartItemDto> DeleteItem(int id);
+        Task<CartItemDto> UpdateQuantity(CartItemQuantityUpdateDto cartItemQuantityUpdateDto);
     }
 }
diff --git a/ShopOnline.Web/Services/ShoppingCartService.cs b/ShopOnline.Web/Services/ShoppingCartService.cs
index 98b80b1..542c95b 100644
--- a/ShopOnline.Web/Services/ShoppingCartService.cs
+++ b/ShopOnline.Web/Services/ShoppingCartService.cs
@@ -1,6 +1,9 @@
-using ShopOnline.Models.Dtos;
+using Newtonsoft.Json;
+using ShopOnline.Models.Dtos;
 using ShopOnline.Web.Services.Contracts;
 using System.Net.Http.Json;
+using System.Text;
+using System.Text.Json.Serialization;
 
 namespace ShopOnline.Web.Services
 {
@@ -82,6 +85,26 @@ namespace ShopOnline.Web.Services
             }
         }
 
+        public async Task<CartItemDto> UpdateQuantity(CartItemQuantityUpdateDto cartItemQuantityUpdateDto)
+        {
+            try
+            {
+                var jsonRequest = JsonConvert.SerializeObject(cartItemQuantityUpdateDto);
+                var content = new StringContent(jsonRequest, Encoding.UTF8, "application/json-patch+json");
 
+                var response = await httpClient.PatchAsync($"api/ShoppingCart/{cartItemQuantityUpdateDto.CartItemId}", content);
+
+                if (response.IsSuccessStatusCode)
+                {
+                    return await response.Content.ReadFromJsonAsync<CartItemDto>();
+                }
+                return null;
+            }
+            catch (Exception)
+            {
+
+                throw;
+            }
+        }
     }
 }
diff --git a/ShopOnline.Web/ShopOnline.Web.csproj b/ShopOnline.Web/ShopOnline.Web.csproj
index 41404a9..9db1809 100644
--- a/ShopOnline.Web/ShopOnline.Web.csproj
+++ b/ShopOnline.Web/ShopOnline.Web.csproj
@@ -9,6 +9,7 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.AspNetCore.Components.WebAssembly" Version="6.0.8" />
     <PackageReference Include="Microsoft.AspNetCore.Components.WebAssembly.DevServer" Version="6.0.8" PrivateAssets="all" />
+    <PackageReference Include="Newtonsoft.Json" Version="13.0.1" />
   </ItemGroup>
 
   <ItemGroup>