ccxt Binance vs Upbit: 47ms Latency Gap in Order Execution

#ccxt #binance #upbit #apilatency

The Order That Arrived 200ms Late

A market order should be instant. That's the whole point. But when the same ccxt create_market_order() call consistently takes 180ms on one exchange and 230ms on another, you start wondering where those milliseconds are going.

I ran into this while debugging a simple arbitrage script between Binance and Upbit. The price difference looked profitable on paper, but by the time the second leg executed, the spread had vanished. The culprit wasn't network jitter or exchange congestion—it was a fundamental difference in how these two exchanges handle order placement through ccxt.

This post breaks down the actual latency numbers from 500 order cycles, the surprising bottleneck that has nothing to do with network round-trip time, and why Upbit's authentication flow adds roughly 47ms to every single request.