The sticker shock is real If you upgraded your production app from GPT-5.4 to GPT-5.5 the day it dropped, your API bill probably gave you a heart attack. OpenAI's listed price doubled: input tokens went from $2.50 to $5 per million, output tokens from $15 to $30. OpenAI's pitch was that GPT-5.5 uses fewer tokens per response, so the net cost should be manageable. According to OpenRouter's real-world usage data from April 2026, that promise only holds for long-context workloads. For inputs over 10,000 tokens, responses are 19-34 percent shorter, which helps. But for the 2,000-10,000 token range that covers most chatbot and agent interactions, responses are actually 52 percent longer . For short prompts under 2,000 tokens — the bread and butter of most API calls — response length barely changed, meaning your cost nearly doubled. The net result: real-world costs jumped 49 to 92 percent depending on your usage pattern. The hallucination tax nobody talks about Cost is only half the story.…