OpenRouter Adds GPT-5.4 Mini and Nano, Optimized for Agent Pipelines

Mar 19, 2026 · Updated Apr 25, 2026

OpenRouter, a unified API for accessing AI models, has added OpenAI's GPT-5.4 mini and nano to its catalog. GPT-5.4 mini handles text and image inputs with strong reasoning, coding, and tool use — priced at $0.75/M input and $4.50/M output tokens. GPT-5.4 nano is the lightest variant, built for classification, data extraction, ranking, and sub-agent execution at $0.20/M input and $1.25/M output. Both carry a 400,000-token context window.

OpenRouter's early testing found mini's speed gains meaningful for coding agents in tight feedback loops and for chat apps that trigger agent tasks mid-conversation. On benchmarks, mini scores 54.4% on SWE-Bench Pro, 72.1% on OSWorld-Verified, and 88.0% on GPQA Diamond.

Switch your OpenRouter model string to openai/gpt-5.4-mini for agent workflows or openai/gpt-5.4-nano for background classification and sub-agent tasks where cost and latency are the primary constraint.

View the full update on openrouter.ai

OpenRouter

@OpenRouterMar 17

The new @OpenAI GPT-5.4 mini and nano are available now on OpenRouter! In our early testing, mini’s increase in speed was useful for staying in the loop for coding agents, and results in better UX for chat apps that allow the models to perform agent tasks mid conversation. https://t.co/E13omKL6RD

View on X