How Netflix Handles Millions of Requests (And Why Your System Probably Can’t Yet)

Most developers build apps that handle hundreds… maybe thousands of requests. But systems like Netflix? They handle millions of concurrent users—streaming video, serving APIs, running recommendations—all in real time. I’ve seen this too many times: people design systems that work fine locally… then collapse the moment real traffic hits. So, the real question is: Why do systems like Netflix survive massive scale while most systems don’t? Let’s break it down—no fluff. ⚙️ 1. Everything Scales Horizontally (Not Vertically) Here’s the first mistake I see everywhere: People try to scale by upgrading servers. That doesn’t work. Netflix-style systems follow one rule: Add more machines, not bigger machines. 🔁 Flow User Requests → Load Balancer → Multiple Services → Databases When traffic increases: New instances spin up Load gets distributed While working on backend systems, I realized quickly that vertical scaling hits a ceiling fast—horizontal scaling is the only real way forward. 🌐 2. Load B