Comprehensive side-by-side LLM comparison
. Both models have their strengths depending on your specific coding needs.
OpenAI
GPT-5 Pro is an extended-reasoning variant from the GPT-5 family that applies more compute per response for deeper, more thorough answers on complex problems. It features the same 400K token context window and multimodal capabilities as GPT-5, with additional reasoning depth suited to research-grade analysis, advanced coding, and tasks requiring comprehensive, accurate outputs.
OpenAI
GPT-5.1 Instant, released by OpenAI in November 2025, is a low-latency variant from the GPT-5.1 family optimized for fast response times and high-throughput workloads. It targets real-time applications, conversational assistants, and production APIs where response speed is a primary requirement alongside GPT-5.1-generation reasoning quality.
2 months newer

GPT-5 Pro
OpenAI
2025-08-07

GPT-5.1 Instant
OpenAI
2025-11
Available providers and their performance metrics
GPT-5 Pro
GPT-5.1 Instant
GPT-5 Pro
GPT-5.1 Instant