Server Error (5xx)
HTTP 503 — 503 Service Unavailable
The server cannot handle the request (because it is overloaded or down for maintenance). Generally, this is a temporary state.
Common Causes & Diagnoses
- •Server CPU or RAM at 100% capacity, database maintenance in progress.
Spesifikasyon & Kategori
Status Code:503
Category:Server Error (5xx)
RFC Standard:RFC 9110 / HTTP/1.1 & HTTP/2
Multi-Language Code Implementations
How to Handle, Return & Test HTTP 503
Status: 503 503 Service Unavailable
server.js / handler.ts
// Express.js Server Response
app.get('/api/resource', (req, res) => {
// Returning 503 503 Service Unavailable
return res.status(503).json({
error: '503 Service Unavailable',
statusCode: 503,
timestamp: new Date().toISOString()
});
});
// Client-side fetch error check
const response = await fetch('/api/resource');
if (response.status === 503) {
console.warn('Received HTTP 503 503 Service Unavailable');
}💡 Pro Tip: Ensure appropriate error handling middleware or proxy interceptors are enabled so client applications receive structured JSON responses for HTTP 503.
How to Fix / Practical Code Solutions
Enable Cloudflare Under Attack Mode or Scale Instances
Scale CPU/RAM or distribute load across multiple servers.
Other Popular HTTP Status Codes
Frequently Asked Questions
Common Questions About HTTP 503 to RFC Standard
Everything you need to know regarding specifications, syntax, and security best practices.
The server cannot handle the request (because it is overloaded or down for maintenance). Generally, this is a temporary state. In Turkish: Sunucu geçici olarak aşırı yük altında veya bakım modundadır.