diff --git a/sim/app/(auth)/verify/page.tsx b/sim/app/(auth)/verify/page.tsx
index 3ec593fd4d..7a2459c8cf 100644
--- a/sim/app/(auth)/verify/page.tsx
+++ b/sim/app/(auth)/verify/page.tsx
@@ -1,10 +1,9 @@
 import { isProd } from '@/lib/environment'
 import { VerifyContent } from './verify-content'
+import { getBaseUrl } from '@/lib/urls/utils'
 
 export default function VerifyPage() {
-  const protocol = isProd ? 'https' : 'http'
-  const appUrl = process.env.NEXT_PUBLIC_APP_URL || 'localhost:3000'
-  const baseUrl = `${protocol}://${appUrl}`
+  const baseUrl = getBaseUrl()
 
   const hasResendKey = Boolean(
     process.env.RESEND_API_KEY && process.env.RESEND_API_KEY !== 'placeholder'
diff --git a/sim/app/api/chat/edit/[id]/route.ts b/sim/app/api/chat/edit/[id]/route.ts
index 24ebcbbee1..7577d6a5e6 100644
--- a/sim/app/api/chat/edit/[id]/route.ts
+++ b/sim/app/api/chat/edit/[id]/route.ts
@@ -7,6 +7,7 @@ import { chat } from '@/db/schema'
 import { createErrorResponse, createSuccessResponse } from '@/app/api/workflows/utils'
 import { z } from 'zod'
 import { encryptSecret } from '@/lib/utils'
+import { getBaseDomain } from '@/lib/urls/utils'
 
 export const dynamic = 'force-dynamic'
 
@@ -67,17 +68,15 @@ export async function GET(
     // Create a new result object without the password
     const { password, ...safeData } = chatInstance[0]
     
-    // Check if we're in development or production
     const isDevelopment = process.env.NODE_ENV === 'development'
+
     const chatUrl = isDevelopment
-      ? `http://${chatInstance[0].subdomain}.localhost:3000`
+      ? `http://${chatInstance[0].subdomain}.${getBaseDomain()}`
       : `https://${chatInstance[0].subdomain}.simstudio.ai`
     
-    // For security, don't return the actual password value
     const result = {
       ...safeData,
       chatUrl,
-      // Include password presence flag but not the actual value
       hasPassword: !!password
     }
     
@@ -228,12 +227,12 @@ export async function PATCH(
         .set(updateData)
         .where(eq(chat.id, chatId))
       
-      // Return success response
       const updatedSubdomain = subdomain || existingChat[0].subdomain
-      // Check if we're in development or production
+      
       const isDevelopment = process.env.NODE_ENV === 'development'
+      
       const chatUrl = isDevelopment
-        ? `http://${updatedSubdomain}.localhost:3000`
+        ? `http://${updatedSubdomain}.${getBaseDomain()}`
         : `https://${updatedSubdomain}.simstudio.ai`
       
       logger.info(`Chat "${chatId}" updated successfully`)
diff --git a/sim/app/w/[id]/components/control-bar/components/deploy-modal/components/chat-deploy/chat-deploy.tsx b/sim/app/w/[id]/components/control-bar/components/deploy-modal/components/chat-deploy/chat-deploy.tsx
index 0ab8cfdef0..fb95ee9d39 100644
--- a/sim/app/w/[id]/components/control-bar/components/deploy-modal/components/chat-deploy/chat-deploy.tsx
+++ b/sim/app/w/[id]/components/control-bar/components/deploy-modal/components/chat-deploy/chat-deploy.tsx
@@ -32,6 +32,7 @@ import { Skeleton } from '@/components/ui/skeleton'
 import { Textarea } from '@/components/ui/textarea'
 import { createLogger } from '@/lib/logs/console-logger'
 import { cn } from '@/lib/utils'
+import { getBaseDomain } from '@/lib/urls/utils'
 import { useNotificationStore } from '@/stores/notifications/store'
 import { OutputSelect } from '@/app/w/[id]/components/panel/components/chat/components/output-select/output-select'
 import { OutputConfig } from '@/stores/panel/chat/types'
@@ -54,6 +55,11 @@ type AuthType = 'public' | 'password' | 'email'
 
 const isDevelopment = process.env.NODE_ENV === 'development'
 
+const getDomainSuffix = (() => {
+  const suffix = isDevelopment ? `.${getBaseDomain()}` : '.simstudio.ai'
+  return () => suffix
+})()
+
 // Define Zod schema for API request validation
 const chatSchema = z.object({
   workflowId: z.string().min(1, 'Workflow ID is required'),
@@ -810,11 +816,20 @@ export function ChatDeploy({
   }
 
   if (deployedChatUrl) {
-    // Extract just the subdomain from the URL
     const url = new URL(deployedChatUrl)
     const hostname = url.hostname
     const isDevelopmentUrl = hostname.includes('localhost')
-    const domainSuffix = isDevelopmentUrl ? '.localhost:3000' : '.simstudio.ai'
+    
+    let domainSuffix
+    if (isDevelopmentUrl) {
+      const baseDomain = getBaseDomain()
+      const baseHost = baseDomain.split(':')[0]
+      const port = url.port || (baseDomain.includes(':') ? baseDomain.split(':')[1] : '3000')
+      domainSuffix = `.${baseHost}:${port}`
+    } else {
+      domainSuffix = '.simstudio.ai'
+    }
+    
     const subdomainPart = isDevelopmentUrl
       ? hostname.split('.')[0]
       : hostname.split('.simstudio.ai')[0]
@@ -911,7 +926,7 @@ export function ChatDeploy({
                     disabled={isDeploying}
                   />
                   <div className="h-10 px-3 flex items-center border border-l-0 rounded-r-md bg-muted text-muted-foreground text-sm font-medium whitespace-nowrap">
-                    {isDevelopment ? '.localhost:3000' : '.simstudio.ai'}
+                    {getDomainSuffix()}
                   </div>
                   {!isCheckingSubdomain && subdomainAvailable === true && subdomain && (
                     <div className="absolute right-14 flex items-center">
diff --git a/sim/lib/urls/utils.ts b/sim/lib/urls/utils.ts
new file mode 100644
index 0000000000..e817b18838
--- /dev/null
+++ b/sim/lib/urls/utils.ts
@@ -0,0 +1,36 @@
+/**
+ * Returns the base URL of the application, respecting environment variables for deployment environments
+ * @returns The base URL string (e.g., 'http://localhost:3000' or 'https://example.com')
+ */
+export function getBaseUrl(): string {
+  if (typeof window !== 'undefined') {
+    return window.location.origin
+  }
+  
+  const baseUrl = process.env.NEXT_PUBLIC_APP_URL
+  if (baseUrl) {
+    if (baseUrl.startsWith('http://') || baseUrl.startsWith('https://')) {
+      return baseUrl
+    }
+    
+    const isProd = process.env.NODE_ENV === 'production'
+    const protocol = isProd ? 'https://' : 'http://'
+    return `${protocol}${baseUrl}`
+  }
+  
+  return 'http://localhost:3000'
+}
+
+/**
+ * Returns just the domain and port part of the application URL
+ * @returns The domain with port if applicable (e.g., 'localhost:3000' or 'simstudio.ai')
+ */
+export function getBaseDomain(): string {
+  try {
+    const url = new URL(getBaseUrl())
+    return url.host // host includes port if specified
+  } catch (e) {
+    const isProd = process.env.NODE_ENV === 'production'
+    return isProd ? 'simstudio.ai' : 'localhost:3000'
+  }
+} 
\ No newline at end of file
diff --git a/sim/middleware.ts b/sim/middleware.ts
index 5eb970f468..393938afb8 100644
--- a/sim/middleware.ts
+++ b/sim/middleware.ts
@@ -2,6 +2,7 @@ import { NextRequest, NextResponse } from 'next/server'
 import { getSessionCookie } from 'better-auth/cookies'
 import { verifyToken } from './lib/waitlist/token'
 import { createLogger } from '@/lib/logs/console-logger'
+import { getBaseDomain } from '@/lib/urls/utils'
 
 const logger = createLogger('Middleware')
 
@@ -15,7 +16,8 @@ const SUSPICIOUS_UA_PATTERNS = [
   /^\(\)\s*{/,                            // Command execution attempt
   /\b(sqlmap|nikto|gobuster|dirb|nmap)\b/i // Known scanning tools
 ]
-const BASE_DOMAIN = isDevelopment ? 'localhost:3000' : 'simstudio.ai'
+
+const BASE_DOMAIN = getBaseDomain()
 
 export async function middleware(request: NextRequest) {
   // Check for active session
diff --git a/sim/tools/http/request.ts b/sim/tools/http/request.ts
index 33158ae051..449538a4aa 100644
--- a/sim/tools/http/request.ts
+++ b/sim/tools/http/request.ts
@@ -1,23 +1,21 @@
 import { HttpMethod, TableRow, ToolConfig } from '../types'
 import { createLogger } from '@/lib/logs/console-logger'
 import { RequestParams, RequestResponse } from './types'
+import { getBaseUrl } from '@/lib/urls/utils'
 
 const logger = createLogger('HTTPRequestTool')
 
 // Function to get the appropriate referer based on environment
 const getReferer = (): string => {
-  // Check if we're in a browser environment
   if (typeof window !== 'undefined') {
     return window.location.origin
   }
   
-  // Use environment variable if available (server-side)
-  if (process.env.NEXT_PUBLIC_APP_URL) {
-    return process.env.NEXT_PUBLIC_APP_URL
+  try {
+    return getBaseUrl()
+  } catch (error) {
+    return 'http://localhost:3000'
   }
-  
-  // Fallback for development
-  return 'http://localhost:3000/'
 }
 
 /**
diff --git a/sim/tools/mistral/parser.ts b/sim/tools/mistral/parser.ts
index 45a0ba9a8a..d856e866b2 100644
--- a/sim/tools/mistral/parser.ts
+++ b/sim/tools/mistral/parser.ts
@@ -1,6 +1,7 @@
 import { createLogger } from '@/lib/logs/console-logger'
 import { ToolConfig } from '../types'
 import { MistralParserInput, MistralParserOutput } from './types'
+import { getBaseUrl } from '@/lib/urls/utils'
 
 const logger = createLogger('MistralParserTool')
 
@@ -97,7 +98,8 @@ export const mistralParserTool: ToolConfig<MistralParserInput, MistralParserOutp
           // Make sure the file path is an absolute URL
           if (uploadedFilePath.startsWith('/')) {
             // If it's a relative path starting with /, convert to absolute URL
-            const baseUrl = process.env.NEXT_PUBLIC_APP_URL || 'http://localhost:3000'
+            const baseUrl = getBaseUrl()
+            if (!baseUrl) throw new Error('Failed to get base URL for file path conversion')
             uploadedFilePath = `${baseUrl}${uploadedFilePath}`
           }
 
diff --git a/sim/tools/openai/dalle.ts b/sim/tools/openai/dalle.ts
index a7a3f7a5dc..6e8bff87b7 100644
--- a/sim/tools/openai/dalle.ts
+++ b/sim/tools/openai/dalle.ts
@@ -1,5 +1,6 @@
 import { ToolConfig } from '../types'
 import { createLogger } from '@/lib/logs/console-logger'
+import { getBaseUrl } from '@/lib/urls/utils'
 
 const logger = createLogger('DalleTool')
 
@@ -79,10 +80,8 @@ export const dalleTool: ToolConfig = {
       logger.info('Using model:', modelName)
 
       try {
-        // Fetch the image using the proxy/image endpoint instead of direct fetch
         logger.info('Fetching image from URL via proxy...')
-        // Get the base URL from environment or use a fallback
-        const baseUrl = process.env.NEXT_PUBLIC_APP_URL || 'http://localhost:3000'
+        const baseUrl = getBaseUrl()
         const proxyUrl = new URL(`/api/proxy/image`, baseUrl)
         proxyUrl.searchParams.append('url', imageUrl)
 
@@ -90,7 +89,7 @@ export const dalleTool: ToolConfig = {
           headers: {
             Accept: 'image/*, */*',
           },
-          cache: 'no-store', // Don't use cache
+          cache: 'no-store',
         })
 
         if (!imageResponse.ok) {