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GPT-5.3-Codex on OpenRouter

GPT-5.4 · OpenAI

Serverless

Get Started with GPT-5.3-Codex on OpenRouter

OpenRouter offers access to GPT-5.3-Codex. Multi-provider LLM aggregator offering unified API access to 300+ models from all major labs and emerging providers, with automatic failover for reliability.

Pricing

TypePrice (per 1M)
Input tokens$1.75
Output tokens$14.00

Capabilities

VisionMultimodalReasoningFunction CallingTool UseStructured OutputsCode Execution

About GPT-5.3-Codex

GPT-5.3-Codex is OpenAI's most capable agentic coding model as of February 2026, combining the Codex and GPT-5 training stacks for advanced code generation, reasoning, and general intelligence. Approximately 25% faster than its predecessors and optimized for steerable coding agents. Predecessor to GPT-5.4. No public parameter count or context window disclosed.

Model Specs

Released2026-02-05
ArchitectureDecoder Only

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