How much does an AI chatbot cost on GPT-5.5?
Running a general-purpose chat assistant on GPT-5.5 costs about $6,053/month for 1,000 users × 15 messages/day: that's $6.05 per user and $13.45 per 1,000 requests.
Monthly$6,053
Per user / mo$6.05
Per 1k requests$13.45
Quality index38.4
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Assumptions
- 1,000 users × 15 messages/day (450,000 per month)
- System prompt 800 tokens, user input 150, output 350 tokens
- Prompt cache hit rate 50%
- GPT-5.5 list price: $5/1M input, $30/1M output, $0.5/1M cached input; context window 1,050,000 tokens
How GPT-5.5 compares for an AI chatbot
14 of 14 other popular models are cheaper for this workload. Cheapest isn't always best: check the quality index, and consider routing easy requests to a cheap model and only hard ones to a frontier model.
| Model | Quality | Monthly | Per user |
|---|---|---|---|
| DeepSeek V4 Flash 0423 | 24.4 | $54.46 | $0.054 |
| GPT-5 Nano | 13 | $76.28 | $0.076 |
| Gemini 2.5 Flash Lite | 10.4 | $86.55 | $0.087 |
| Claude Haiku 5.5 | 43.4 | $110 | $0.11 |
| Llama 4 Maverick | 9.3 | $158 | $0.16 |
| DeepSeek V4 Pro 0423 | 30.4 | $223 | $0.22 |
| Gemini 3.8 Flash | 40.9 | $728 | $0.73 |
| Grok 4.3 | 24.9 | $739 | $0.74 |
| GPT-5.4 Mini | 24.1 | $908 | $0.91 |
| Grok 4.7 | 46.4 | $1,530 | $1.53 |
| Gemini 4 Argon | 52.6 | $1,762 | $1.76 |
| GPT-6.1 Sol | 51.8 | $2,178 | $2.18 |
| Claude Sonnet 5.5 | 56 | $2,178 | $2.18 |
| Claude Opus 5.5 | 57.6 | $4,356 | $4.36 |
| GPT-5.5 | 38.4 | $6,053 | $6.05 |
More GPT-5.5 cost guides
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Prices: OpenRouter list prices (USD per 1M tokens), updated 2026-10-15. Estimates only; a month is 30 days. See how the math works.