HTTP 500 Internal Server Error — Causes, Debugging & Fix Guide

When to Return 500

Return 500 when an unexpected exception occurs that you haven't handled with a more specific status code. Always log the full error server-side. Return a generic error message to the client — never expose stack traces in production.

Common Causes

• Unhandled exception or promise rejection
• Database connection error
• Null pointer dereference or type error
• Out of memory error
• Third-party service returning unexpected data

HTTP Response Example

HTTP/1.1 500 Internal Server Error
Content-Type: application/json

{"error": "Internal Server Error"}

Code Examples

// Global error handler (must have 4 parameters)
app.use((err, req, res, next) => {
  console.error({
    message: err.message,
    stack: err.stack,
    url: req.url,
    method: req.method,
  })

  // Never expose stack traces in production
  res.status(err.status ?? 500).json({
    error: process.env.NODE_ENV === 'production'
      ? 'Internal Server Error'
      : err.message,
  })
})

// app/error.tsx — catches runtime errors in the component tree
'use client'
export default function Error({ error, reset }) {
  return (
    <div>
      <h2>Something went wrong</h2>
      <button onClick={reset}>Try again</button>
    </div>
  )
}

// app/api/route.ts — wrap handlers in try/catch
export async function GET() {
  try {
    const data = await fetchData()
    return Response.json(data)
  } catch (err) {
    console.error(err)
    return Response.json({ error: 'Internal Server Error' }, { status: 500 })
  }
}

Related Status Codes