The o-series of models are trained with reinforcement learning to think before they answer and perform complex reasoning. The o3-pro model uses more compute to think harder and provide consistently...
Why it stands out
What to watch
Release timeline
release
The o-series of models are trained with reinforcement learning to think before they answer and perform complex reasoning. The o3-pro model uses more compute to think harder and provide consistently better answers. Note that BYOK is required for this model. Set up here: https://openrouter.ai/settings/integrations
View sourceNearby alternatives
GPT-5.4 nano is the most lightweight and cost-efficient variant of the GPT-5.4 family, optimized for speed-critical and high-volume tasks. I
GPT-5.4 mini brings the core capabilities of GPT-5.4 to a faster, more efficient model optimized for high-throughput workloads. It supports
GPT-5.4 Pro is OpenAI's most advanced model, building on GPT-5.4's unified architecture with enhanced reasoning capabilities for complex, hi
GPT-5.4 is OpenAI’s latest frontier model, unifying the Codex and GPT lines into a single system. It features a 1M+ token context window (92
OpenAI launched OpenAI: o3 Pro
Compare
vs Anthropic: Claude 3.5 Sonnet
Side-by-side pricing, context, and capabilities
vs Anthropic: Claude 3.7 Sonnet (thinking)
Side-by-side pricing, context, and capabilities
vs Anthropic: Claude 3.7 Sonnet
Side-by-side pricing, context, and capabilities
vs Anthropic: Claude Opus 4.1
Side-by-side pricing, context, and capabilities
vs Anthropic: Claude Opus 4.5
Side-by-side pricing, context, and capabilities
vs Anthropic: Claude Opus 4.6
Side-by-side pricing, context, and capabilities