OpenAI Launches GPT-4.1 Family via API, Boosting Coding and Long-Context Capabilities for Developers

On April 14, 2025, OpenAI launched the GPT-4.1 model family, which includes GPT-4.1, GPT-4.1-mini, and GPT-4.1-nano. These models are made available via API and selected platforms like Microsoft Azure and GitHub Copilot, rather than being directly integrated into the ChatGPT consumer product at launch. The release is specifically designed for developers, focusing on improvements in performance, reliability, cost-efficiency, and long-context understanding.

A key advancement in GPT-4.1 is its superior coding ability. The flagship model demonstrated substantial gains in software engineering benchmarks, significantly outperforming earlier models in code editing tasks and frontend development. For example, it halved the rate of unnecessary code changes compared to its predecessor and was preferred in web generation comparisons by human reviewers. Additionally, the output token limit has been increased to 32,768 tokens, doubling previous capacities for large code tasks.

Instruction-following capabilities have also been upgraded. The new models perform better in understanding complex, multi-step prompts and consistently maintain formatting and structure across responses. These upgrades are especially useful for developers building AI agents, which require precise and reliable execution of tasks.

Perhaps the most striking feature is the introduction of a 1 million token context window across all GPT-4.1 variants. This allows the models to handle significantly larger inputs—such as full codebases or extensive documents—within a single interaction. Internal tests show that the models maintain focus and accuracy throughout this extended context.

The GPT-4.1 family offers three options tailored to different needs and budgets:

• GPT-4.1 is the most powerful, ideal for advanced coding and complex workflows.

• GPT-4.1-mini balances performance with cost, achieving similar benchmarks to GPT-4o but at 83% lower cost and with reduced latency.

• GPT-4.1-nano focuses on speed and affordability, optimized for tasks like classification and document processing, while still supporting the full context window.

Pricing reflects this tiered approach, with GPT-4.1-nano being the most economical and GPT-4.1 providing the highest performance. OpenAI also plans to offer fine-tuning options for GPT-4.1 and GPT-4.1-mini, allowing developers to adapt the models to specific use cases using custom data.

Coinciding with this release, OpenAI announced the upcoming retirement of GPT-4.5 Preview, which will be deprecated in July 2025. GPT-4.1 is positioned as its successor, providing superior performance at a lower cost and with better latency.

Overall, the GPT-4.1 series reflects OpenAI’s continued push toward more capable and developer-friendly AI tools. By offering models that improve coding, follow instructions more reliably, and handle much larger inputs, the company is reinforcing its commitment to supporting innovation in AI development through accessible and efficient APIs.