Fix Vercel Function Timeout in Next.js API Routes

A timeout means the serverless function did not return within the platform limit. Start by finding the slow network call or database query in runtime logs.

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Common symptoms

API route returns 504 or FUNCTION_INVOCATION_TIMEOUT.
The route works locally but hangs in production.
Long AI, scraping, or database operations fail after deploy.

What to check first

Platform: Vercel + Next.js
Error: Function timeout

A timeout means the serverless function did not return within the platform limit. Start by finding the slow network call or database query in runtime logs.

Step-by-step fix

Open Vercel Function Logs and identify the slow route.
Add timing logs around database, fetch, and AI API calls.
Return early for background work or move long jobs to a queue.
Set route runtime/max duration only if your plan and framework support it.

console.time("db");
const rows = await db.query(...);
console.timeEnd("db");

Common mistake to avoid

Do not hide timeouts with retries. Fix the slow operation or move it off the request path.

Still stuck?

Send the deploy log, repository link, target platform, and expected URL. ShipFast Deploy Rescue is a fixed-price debugging service for indie projects and MVPs.

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