GPT-5.5 Price Increase: What It Costs (openrouter.ai)

The recent launch of OpenAI's GPT-5.5 has come with a significant price increase—doubling the costs of input and output tokens compared to its predecessor, GPT-5.4. Input tokens are now priced at $5.00/M and output tokens at $30/M. However, initial analyses indicate that while overall costs for users who switched from GPT-5.4 to GPT-5.5 increased between 49-92%, the model's reduced verbosity for longer prompts (over 10,000 tokens) helped offset some of these costs, generating 19-34% fewer completion tokens for these cases. This price adjustment marks a crucial moment in the AI/ML landscape, prompting users to reassess their cost-effectiveness when transitioning to newer models. The methodology employed involved a "switcher cohort" analysis, which provided insights based on direct comparisons across user workflows. The findings reveal that for shorter prompts (under 10,000 tokens), costs are significantly higher, as the completion lengths have not decreased. Conversely, for longer prompts, users might find some financial relief due to more concise outputs, raising questions about efficiency and the value proposition of upgrading to GPT-5.5 for different use cases.