CORS: No ‘Access-Control-Allow-Origin’ header in Express app (Node.js 24)

[anshumanb (Anshuman Bhardwaj)]

Hi @cubasve, I see. I’d recommend giving this post a read:

Different ways to handle CORS on Vercel

Cross-Origin Resource Sharing (CORS) issues are common when you are hosting your backend and frontend applications on different origins. Browsers implement the CORS mechanism as a safeguard to prevent applications on a different origin from loading your resources. This is why it is important to set up your backend application with the correct CORS configuration. Getting Started When using Vercel, you can configure CORS headers in the following ways: Using the Vercel project configuration Usi…

Similarly I go into details about Express and CORS here:

https://community.vercel.com/t/express-101-everything-about-deploying-your-express-app-on-vercel/4870/2

I recommend you look at it from a fresh perspective and see if the repos linked work and then work backwards in your project to debug.