diff --git a/server/PlanShare/.gitignore b/server/PlanShare/.gitignore
new file mode 100644
index 0000000..337ba47
--- /dev/null
+++ b/server/PlanShare/.gitignore
@@ -0,0 +1,3 @@
+bin/
+obj/
+data/
diff --git a/server/PlanShare/PlanShare.csproj b/server/PlanShare/PlanShare.csproj
new file mode 100644
index 0000000..854439d
--- /dev/null
+++ b/server/PlanShare/PlanShare.csproj
@@ -0,0 +1,13 @@
+<Project Sdk="Microsoft.NET.Sdk.Web">
+
+  <PropertyGroup>
+    <TargetFramework>net8.0</TargetFramework>
+    <Nullable>enable</Nullable>
+    <ImplicitUsings>enable</ImplicitUsings>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.Data.Sqlite" Version="10.0.5" />
+  </ItemGroup>
+
+</Project>
diff --git a/server/PlanShare/Program.cs b/server/PlanShare/Program.cs
new file mode 100644
index 0000000..d321c6c
--- /dev/null
+++ b/server/PlanShare/Program.cs
@@ -0,0 +1,242 @@
+using System.Collections.Concurrent;
+using System.Security.Cryptography;
+using System.Text.Json;
+using Microsoft.Data.Sqlite;
+
+var builder = WebApplication.CreateBuilder(args);
+
+// CORS — allow all origins for WASM client
+builder.Services.AddCors(options =>
+{
+    options.AddDefaultPolicy(policy =>
+        policy.AllowAnyOrigin().AllowAnyMethod().AllowAnyHeader());
+});
+
+// Database path — data/ subdirectory relative to the binary
+var dataDir = Path.Combine(AppContext.BaseDirectory, "data");
+Directory.CreateDirectory(dataDir);
+var dbPath = Path.Combine(dataDir, "plans.db");
+var connectionString = $"Data Source={dbPath}";
+
+// Initialize database
+using (var conn = new SqliteConnection(connectionString))
+{
+    conn.Open();
+    using var cmd = conn.CreateCommand();
+    cmd.CommandText = """
+        CREATE TABLE IF NOT EXISTS plans (
+            id TEXT PRIMARY KEY,
+            data TEXT NOT NULL,
+            created_at TEXT NOT NULL,
+            expires_at TEXT NOT NULL,
+            delete_token TEXT NOT NULL
+        )
+        """;
+    cmd.ExecuteNonQuery();
+}
+
+// Register the cleanup background service
+builder.Services.AddSingleton(new PlanDbConfig(connectionString));
+builder.Services.AddHostedService<CleanupService>();
+
+// Request size limit (10 MB)
+builder.WebHost.ConfigureKestrel(o => o.Limits.MaxRequestBodySize = 10 * 1024 * 1024);
+
+var app = builder.Build();
+app.UseCors();
+
+// --- Rate limiter: 10 shares per minute per IP (in-memory) ---
+var rateLimiter = new RateLimiter(maxRequests: 10, windowSeconds: 60);
+
+const int MaxTtlDays = 365;
+
+// --- Endpoints ---
+
+app.MapGet("/health", () => Results.Content("OK", "text/plain"));
+
+app.MapPost("/api/share", async (HttpContext ctx) =>
+{
+    // Rate limit by IP
+    var ip = ctx.Connection.RemoteIpAddress?.ToString() ?? "unknown";
+    if (!rateLimiter.IsAllowed(ip))
+    {
+        return Results.StatusCode(429);
+    }
+
+    // Read raw body
+    using var reader = new StreamReader(ctx.Request.Body);
+    var body = await reader.ReadToEndAsync();
+
+    if (string.IsNullOrWhiteSpace(body))
+    {
+        return Results.BadRequest("Empty body");
+    }
+
+    // Parse and extract ttl_days from the JSON
+    int ttlDays = 7;
+    try
+    {
+        using var doc = JsonDocument.Parse(body);
+        if (doc.RootElement.TryGetProperty("ttl_days", out var ttlProp) && ttlProp.TryGetInt32(out var t))
+            ttlDays = Math.Clamp(t, 1, MaxTtlDays);
+    }
+    catch (JsonException)
+    {
+        return Results.BadRequest("Invalid JSON");
+    }
+
+    var id = GenerateId();
+    var deleteToken = GenerateDeleteToken();
+    var now = DateTime.UtcNow;
+    var expiresAt = now.AddDays(ttlDays);
+
+    using var conn = new SqliteConnection(connectionString);
+    conn.Open();
+    using var cmd = conn.CreateCommand();
+    cmd.CommandText = "INSERT INTO plans (id, data, created_at, expires_at, delete_token) VALUES (@id, @data, @created_at, @expires_at, @delete_token)";
+    cmd.Parameters.AddWithValue("@id", id);
+    cmd.Parameters.AddWithValue("@data", body);
+    cmd.Parameters.AddWithValue("@created_at", now.ToString("o"));
+    cmd.Parameters.AddWithValue("@expires_at", expiresAt.ToString("o"));
+    cmd.Parameters.AddWithValue("@delete_token", deleteToken);
+    cmd.ExecuteNonQuery();
+
+    return Results.Content(
+        $"{{\"id\":\"{id}\",\"delete_token\":\"{deleteToken}\",\"expires_at\":\"{expiresAt:yyyy-MM-dd}\"}}",
+        "application/json");
+});
+
+app.MapGet("/api/plans/{id}", (string id) =>
+{
+    using var conn = new SqliteConnection(connectionString);
+    conn.Open();
+    using var cmd = conn.CreateCommand();
+    cmd.CommandText = "SELECT data FROM plans WHERE id = @id AND expires_at > @now";
+    cmd.Parameters.AddWithValue("@id", id);
+    cmd.Parameters.AddWithValue("@now", DateTime.UtcNow.ToString("o"));
+
+    var result = cmd.ExecuteScalar() as string;
+    if (result is null)
+    {
+        return Results.NotFound();
+    }
+
+    return Results.Content(result, "application/json");
+});
+
+app.MapDelete("/api/plans/{id}", (string id, HttpContext ctx) =>
+{
+    var token = ctx.Request.Query["token"].FirstOrDefault();
+    if (string.IsNullOrEmpty(token))
+    {
+        return Results.BadRequest("Missing delete token");
+    }
+
+    using var conn = new SqliteConnection(connectionString);
+    conn.Open();
+    using var cmd = conn.CreateCommand();
+    cmd.CommandText = "DELETE FROM plans WHERE id = @id AND delete_token = @token";
+    cmd.Parameters.AddWithValue("@id", id);
+    cmd.Parameters.AddWithValue("@token", token);
+    var deleted = cmd.ExecuteNonQuery();
+
+    return deleted > 0 ? Results.Ok() : Results.NotFound();
+});
+
+app.Run();
+
+// --- Helpers ---
+
+static string GenerateId()
+{
+    const string chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
+    return new string(Random.Shared.GetItems<char>(chars.AsSpan(), 8));
+}
+
+static string GenerateDeleteToken()
+{
+    return Convert.ToHexString(RandomNumberGenerator.GetBytes(16)).ToLower();
+}
+
+// --- Supporting types ---
+
+record PlanDbConfig(string ConnectionString);
+
+sealed class CleanupService : BackgroundService
+{
+    private readonly PlanDbConfig _config;
+    private readonly ILogger<CleanupService> _logger;
+
+    public CleanupService(PlanDbConfig config, ILogger<CleanupService> logger)
+    {
+        _config = config;
+        _logger = logger;
+    }
+
+    protected override async Task ExecuteAsync(CancellationToken stoppingToken)
+    {
+        Cleanup();
+
+        using var timer = new PeriodicTimer(TimeSpan.FromHours(1));
+        while (await timer.WaitForNextTickAsync(stoppingToken))
+        {
+            Cleanup();
+        }
+    }
+
+    private void Cleanup()
+    {
+        try
+        {
+            var now = DateTime.UtcNow.ToString("o");
+            using var conn = new SqliteConnection(_config.ConnectionString);
+            conn.Open();
+            using var cmd = conn.CreateCommand();
+            cmd.CommandText = "DELETE FROM plans WHERE expires_at < @now";
+            cmd.Parameters.AddWithValue("@now", now);
+            var deleted = cmd.ExecuteNonQuery();
+            if (deleted > 0)
+            {
+                _logger.LogInformation("Cleaned up {Count} expired plans", deleted);
+            }
+        }
+        catch (Exception ex)
+        {
+            _logger.LogError(ex, "Error during plan cleanup");
+        }
+    }
+}
+
+sealed class RateLimiter
+{
+    private readonly int _maxRequests;
+    private readonly int _windowSeconds;
+    private readonly ConcurrentDictionary<string, List<DateTime>> _requests = new();
+
+    public RateLimiter(int maxRequests, int windowSeconds)
+    {
+        _maxRequests = maxRequests;
+        _windowSeconds = windowSeconds;
+    }
+
+    public bool IsAllowed(string key)
+    {
+        var now = DateTime.UtcNow;
+        var cutoff = now.AddSeconds(-_windowSeconds);
+
+        var timestamps = _requests.GetOrAdd(key, _ => new List<DateTime>());
+
+        lock (timestamps)
+        {
+            timestamps.RemoveAll(t => t < cutoff);
+
+            if (timestamps.Count >= _maxRequests)
+            {
+                return false;
+            }
+
+            timestamps.Add(now);
+            return true;
+        }
+    }
+}
diff --git a/server/PlanShare/Properties/launchSettings.json b/server/PlanShare/Properties/launchSettings.json
new file mode 100644
index 0000000..26c588f
--- /dev/null
+++ b/server/PlanShare/Properties/launchSettings.json
@@ -0,0 +1,38 @@
+{
+  "$schema": "http://json.schemastore.org/launchsettings.json",
+  "iisSettings": {
+    "windowsAuthentication": false,
+    "anonymousAuthentication": true,
+    "iisExpress": {
+      "applicationUrl": "http://localhost:60802",
+      "sslPort": 44322
+    }
+  },
+  "profiles": {
+    "http": {
+      "commandName": "Project",
+      "dotnetRunMessages": true,
+      "launchBrowser": true,
+      "applicationUrl": "http://localhost:5271",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    },
+    "https": {
+      "commandName": "Project",
+      "dotnetRunMessages": true,
+      "launchBrowser": true,
+      "applicationUrl": "https://localhost:7060;http://localhost:5271",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    },
+    "IIS Express": {
+      "commandName": "IISExpress",
+      "launchBrowser": true,
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    }
+  }
+}
diff --git a/server/PlanShare/appsettings.Development.json b/server/PlanShare/appsettings.Development.json
new file mode 100644
index 0000000..ff66ba6
--- /dev/null
+++ b/server/PlanShare/appsettings.Development.json
@@ -0,0 +1,8 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.AspNetCore": "Warning"
+    }
+  }
+}
diff --git a/server/PlanShare/appsettings.json b/server/PlanShare/appsettings.json
new file mode 100644
index 0000000..4d56694
--- /dev/null
+++ b/server/PlanShare/appsettings.json
@@ -0,0 +1,9 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.AspNetCore": "Warning"
+    }
+  },
+  "AllowedHosts": "*"
+}
diff --git a/src/PlanViewer.Web/Pages/Index.razor b/src/PlanViewer.Web/Pages/Index.razor
index 7fa47bf..91154d3 100644
--- a/src/PlanViewer.Web/Pages/Index.razor
+++ b/src/PlanViewer.Web/Pages/Index.razor
@@ -47,6 +47,7 @@ else
     <div class="toolbar">
         <button class="back-btn" @onclick="Reset">New Plan</button>
         <button class="back-btn" @onclick="ExportHtml">Export HTML</button>
+        <button class="share-btn" @onclick="ShowShareDialog" disabled="@isSharing">Share</button>
         <span class="toolbar-source">@sourceLabel</span>
         <span class="toolbar-plan-type @(result.Summary.HasActualStats ? "actual" : "estimated")">
             @(result.Summary.HasActualStats ? "Actual Plan" : "Estimated Plan")
@@ -55,8 +56,60 @@ else
         {
             <span class="toolbar-version">@result.SqlServerBuild</span>
         }
+        @if (shareUrl != null)
+        {
+            <span class="share-url"><a href="@shareUrl" target="_blank">@shareUrl</a></span>
+        }
+        @if (deleteToken != null)
+        {
+            <button class="delete-share-btn" @onclick="DeleteSharedPlan" disabled="@isDeleting">
+                @(isDeleting ? "Deleting..." : "Delete Share")
+            </button>
+        }
     </div>
 
+    @if (sharePhase == 1)
+    {
+        <div class="modal-overlay" @onclick="HideShareDialog">
+            <div class="modal" @onclick:stopPropagation="true">
+                <h3>Share Plan Analysis</h3>
+                <p>Your plan analysis will be uploaded and stored on a server. Anyone with the link can view the full analysis, including query text, operator details, and warnings.</p>
+                <div class="ttl-picker">
+                    <label>Expire after:</label>
+                    <select @bind="shareTtlDays">
+                        <option value="1">1 day</option>
+                        <option value="7">7 days</option>
+                        <option value="30">30 days</option>
+                        <option value="90">90 days</option>
+                        <option value="180">6 months</option>
+                        <option value="365">1 year</option>
+                    </select>
+                </div>
+                <div class="modal-actions">
+                    <button class="back-btn" @onclick="HideShareDialog">Cancel</button>
+                    <button class="analyze-btn" @onclick="AdvanceSharePhase">Continue</button>
+                </div>
+            </div>
+        </div>
+    }
+
+    @if (sharePhase == 2)
+    {
+        <div class="modal-overlay" @onclick="HideShareDialog">
+            <div class="modal" @onclick:stopPropagation="true">
+                <h3>Confirm Share</h3>
+                <p>You are about to share your plan analysis publicly for <strong>@FormatTtl(shareTtlDays)</strong>.</p>
+                <p>This cannot be undone after you leave this page. Are you sure?</p>
+                <div class="modal-actions">
+                    <button class="back-btn" @onclick="() => sharePhase = 1">Back</button>
+                    <button class="analyze-btn" @onclick="SharePlan" disabled="@isSharing">
+                        @(isSharing ? "Sharing..." : "Yes, Share")
+                    </button>
+                </div>
+            </div>
+        </div>
+    }
+
     @* Statement selector for multi-statement plans *@
     @if (result.Statements.Count > 1)
     {
@@ -1581,6 +1634,8 @@ else
 }
 
 @code {
+    private const string ShareApiBase = "http://87.99.137.152:8080";
+
     private string activeTab = "paste";
     private string planXml = "";
     private string? errorMessage;
@@ -1590,6 +1645,13 @@ else
     private string? textOutput;
     private string? sourceLabel;
     private int activeStatement = 0;
+    private int sharePhase; // 0=hidden, 1=consent, 2=confirm
+    private bool isSharing;
+    private bool isDeleting;
+    private string? shareUrl;
+    private string? shareId;
+    private string? deleteToken;
+    private int shareTtlDays = 7;
     private PlanNode? selectedNode;
 
     private StatementResult? ActiveStmt => result?.Statements.ElementAtOrDefault(activeStatement);
@@ -1686,6 +1748,10 @@ else
         planXml = "";
         activeStatement = 0;
         selectedNode = null;
+        shareUrl = null;
+        shareId = null;
+        deleteToken = null;
+        sharePhase = 0;
     }
 
     private async Task ExportHtml()
@@ -1698,6 +1764,148 @@ else
         await JS.InvokeVoidAsync("downloadFile", fileName, html);
     }
 
+    private void ShowShareDialog()
+    {
+        sharePhase = 1;
+        shareTtlDays = 7;
+    }
+
+    private void HideShareDialog() => sharePhase = 0;
+    private void AdvanceSharePhase() => sharePhase = 2;
+
+    private async Task SharePlan()
+    {
+        if (result == null || textOutput == null) return;
+        isSharing = true;
+        sharePhase = 0;
+        errorMessage = null;
+        StateHasChanged();
+
+        try
+        {
+            using var http = new HttpClient();
+            var payload = System.Text.Json.JsonSerializer.Serialize(new
+            {
+                result = result,
+                text = textOutput,
+                ttl_days = shareTtlDays
+            });
+            var content = new StringContent(payload, System.Text.Encoding.UTF8, "application/json");
+            var response = await http.PostAsync($"{ShareApiBase}/api/share", content);
+
+            if (!response.IsSuccessStatusCode)
+            {
+                errorMessage = $"Share failed: server returned {(int)response.StatusCode}";
+                return;
+            }
+
+            var json = await response.Content.ReadAsStringAsync();
+            using var doc = System.Text.Json.JsonDocument.Parse(json);
+            shareId = doc.RootElement.GetProperty("id").GetString();
+            deleteToken = doc.RootElement.GetProperty("delete_token").GetString();
+            var baseUrl = await JS.InvokeAsync<string>("getBaseUrl");
+            shareUrl = $"{baseUrl}?share={shareId}";
+            await JS.InvokeVoidAsync("copyToClipboard", shareUrl);
+        }
+        catch (Exception ex)
+        {
+            errorMessage = $"Share failed: {ex.Message}";
+        }
+        finally
+        {
+            isSharing = false;
+        }
+    }
+
+    private async Task DeleteSharedPlan()
+    {
+        if (shareId == null || deleteToken == null) return;
+        isDeleting = true;
+        StateHasChanged();
+
+        try
+        {
+            using var http = new HttpClient();
+            var response = await http.DeleteAsync($"{ShareApiBase}/api/plans/{shareId}?token={deleteToken}");
+            if (response.IsSuccessStatusCode)
+            {
+                shareUrl = null;
+                shareId = null;
+                deleteToken = null;
+                errorMessage = null;
+            }
+            else
+            {
+                errorMessage = "Failed to delete shared plan.";
+            }
+        }
+        catch (Exception ex)
+        {
+            errorMessage = $"Delete failed: {ex.Message}";
+        }
+        finally
+        {
+            isDeleting = false;
+        }
+    }
+
+    private static string FormatTtl(int days) => days switch
+    {
+        1 => "1 day",
+        < 30 => $"{days} days",
+        30 => "1 month",
+        90 => "3 months",
+        180 => "6 months",
+        365 => "1 year",
+        _ => $"{days} days"
+    };
+
+    protected override async Task OnInitializedAsync()
+    {
+        var uri = await JS.InvokeAsync<string>("getQueryParam", "share");
+        if (!string.IsNullOrEmpty(uri))
+        {
+            await LoadSharedPlan(uri);
+        }
+    }
+
+    private async Task LoadSharedPlan(string id)
+    {
+        isAnalyzing = true;
+        StateHasChanged();
+
+        try
+        {
+            using var http = new HttpClient();
+            var response = await http.GetAsync($"{ShareApiBase}/api/plans/{id}");
+            if (!response.IsSuccessStatusCode)
+            {
+                errorMessage = response.StatusCode == System.Net.HttpStatusCode.NotFound
+                    ? "This shared plan has expired or does not exist."
+                    : $"Failed to load shared plan: {(int)response.StatusCode}";
+                isAnalyzing = false;
+                return;
+            }
+
+            var json = await response.Content.ReadAsStringAsync();
+            using var doc = System.Text.Json.JsonDocument.Parse(json);
+            var root = doc.RootElement;
+
+            result = System.Text.Json.JsonSerializer.Deserialize<AnalysisResult>(
+                root.GetProperty("result").GetRawText());
+            textOutput = root.GetProperty("text").GetString();
+            sourceLabel = "shared plan";
+        }
+        catch (Exception ex)
+        {
+            errorMessage = $"Failed to load shared plan: {ex.Message}";
+        }
+        finally
+        {
+            isAnalyzing = false;
+        }
+    }
+
     private RenderFragment RenderPlanNodes(PlanNode node, bool isRoot) => builder =>
     {
         var height = PlanLayoutEngine.GetNodeHeight(node);
diff --git a/src/PlanViewer.Web/wwwroot/css/app.css b/src/PlanViewer.Web/wwwroot/css/app.css
index 95b0cb4..0e5569e 100644
--- a/src/PlanViewer.Web/wwwroot/css/app.css
+++ b/src/PlanViewer.Web/wwwroot/css/app.css
@@ -284,6 +284,129 @@ textarea::placeholder {
     color: var(--accent);
 }
 
+.share-btn {
+    padding: 0.3rem 0.75rem;
+    background: var(--accent);
+    color: #fff;
+    border: 1px solid var(--accent);
+    border-radius: 4px;
+    cursor: pointer;
+    font-family: inherit;
+    font-size: 0.8rem;
+}
+
+.share-btn:hover:not(:disabled) {
+    background: var(--accent-hover);
+}
+
+.share-btn:disabled {
+    opacity: 0.5;
+    cursor: default;
+}
+
+.share-url {
+    font-size: 0.8rem;
+    margin-left: auto;
+}
+
+.share-url a {
+    color: var(--accent);
+    text-decoration: none;
+    font-weight: 500;
+}
+
+.share-url a:hover {
+    text-decoration: underline;
+}
+
+/* Share consent modal */
+.modal-overlay {
+    position: fixed;
+    inset: 0;
+    background: rgba(0, 0, 0, 0.5);
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    z-index: 1000;
+}
+
+.modal {
+    background: var(--bg);
+    border-radius: 8px;
+    padding: 1.5rem;
+    max-width: 480px;
+    width: 90%;
+    box-shadow: 0 4px 24px rgba(0, 0, 0, 0.2);
+}
+
+.modal h3 {
+    font-size: 1.1rem;
+    margin-bottom: 0.75rem;
+}
+
+.modal p {
+    font-size: 0.9rem;
+    color: var(--text-secondary);
+    margin-bottom: 0.5rem;
+    line-height: 1.5;
+}
+
+.modal-actions {
+    display: flex;
+    gap: 0.75rem;
+    justify-content: flex-end;
+    margin-top: 1rem;
+}
+
+.modal-actions button {
+    padding: 0.6rem 1.5rem;
+    font-size: 0.9rem;
+}
+
+.ttl-picker {
+    display: flex;
+    align-items: center;
+    gap: 0.5rem;
+    margin-top: 0.75rem;
+    font-size: 0.9rem;
+}
+
+.ttl-picker label {
+    color: var(--text-secondary);
+    font-weight: 500;
+}
+
+.ttl-picker select {
+    padding: 0.3rem 0.5rem;
+    border: 1px solid var(--border);
+    border-radius: 4px;
+    font-family: inherit;
+    font-size: 0.85rem;
+    background: var(--bg);
+    color: var(--text);
+}
+
+.delete-share-btn {
+    padding: 0.3rem 0.75rem;
+    background: none;
+    color: var(--critical);
+    border: 1px solid var(--critical);
+    border-radius: 4px;
+    cursor: pointer;
+    font-family: inherit;
+    font-size: 0.8rem;
+}
+
+.delete-share-btn:hover:not(:disabled) {
+    background: var(--critical);
+    color: #fff;
+}
+
+.delete-share-btn:disabled {
+    opacity: 0.5;
+    cursor: default;
+}
+
 .toolbar-source {
     font-size: 0.85rem;
     color: var(--text);
diff --git a/src/PlanViewer.Web/wwwroot/index.html b/src/PlanViewer.Web/wwwroot/index.html
index a9b9670..079a21e 100644
--- a/src/PlanViewer.Web/wwwroot/index.html
+++ b/src/PlanViewer.Web/wwwroot/index.html
@@ -33,6 +33,15 @@
             document.body.removeChild(a);
             URL.revokeObjectURL(url);
         }
+        function getBaseUrl() {
+            return window.location.origin + window.location.pathname;
+        }
+        function getQueryParam(name) {
+            return new URLSearchParams(window.location.search).get(name) || '';
+        }
+        function copyToClipboard(text) {
+            navigator.clipboard.writeText(text).catch(() => {});
+        }
     </script>
 </body>
 </html>