How Much Does an LLM Chatbot Cost per Month?
At production volume (200,000 calls/month), the cheapest effective option is Amazon Nova Micro at $24.25/month. The most expensive frontier option, GPT-5.4 Pro, runs $27,504/month — A support or product chatbot re-sends a growing conversation history on every turn, so the input side of the bill grows even though each individual reply stays short.
How much does llm chatbot cost per month?
At production volume (200,000 calls/month), the cheapest effective option for llm chatbot is Amazon Nova Micro at $24.25 per month, verbosity-adjusted rather than list price. The most expensive frontier model, GPT-5.4 Pro, runs $27,504 per month for the same workload.
Token shape
| Shape | growing conversation history in, short reply out |
| Input / output tokens per call | 2K in / 0K out |
| Cacheable input | 35% |
| Batch-eligible | No |
Input is a system prompt plus roughly 8-10 turns of history by the middle of a conversation; output is a typical single-paragraph reply. Only the system prompt is stable enough to cache.
Volume
Ranked cost — Production volume
| Model | Provider | List monthly | Effective monthly | Verbosity | Rank Δ |
|---|---|---|---|---|---|
| Amazon Nova Microbudget | Amazon | $26.60 | $18.96 | 0.76× | — |
| Llama 3.1 8Bbudgetlegacy | Groq | $29.60 | $28.31 | 0.77× | — |
| Amazon Nova Litebudget | Amazon | $45.60 | $35.18 | 0.92× | — |
| GPT-5 Nanobudgetlegacy | OpenAI | $52.00 | $44.44 | — | — |
| Gemini 2.5 Flash Litebudgetlegacy | $76.00 | $60.88 | — | ▲1 | |
| Ministral 8Bbudget | Mistral | $82.50 | $81.77 | 0.93× | ▲1 |
| GPT-OSS 20Bbudget | Groq | $57.00 | $97.53 | 2.93× | ▼2 |
| Mistral Small 3.1budget | Mistral | $114 | $108 | 0.85× | ▲4 |
| GPT-4o Minibudgetlegacy | OpenAI | $114 | $91.32 | — | — |
| Grok-3 Minibudgetlegacy | xAI | $114 | $114 | — | — |
| DeepSeek V4 Flashbudget | DeepSeek | $86.80 | $96.99 | 2.60× | ▼3 |
| Llama 4 Maverickbudgetlegacy | Groq | $138 | $138 | — | ▲1 |
| GPT-OSS 120Bbudget | Groq | $114 | $149 | 1.83× | ▼2 |
| GPT-5.4 Nanobudgetlegacy | OpenAI | $184 | $135 | 0.79× | ▲1 |
| GPT-5.6 Lunabudget | OpenAI | $180 | $150 | — | ▼1 |
Show all 63 models
| Codestralbudget | Mistral | $207 | $194 | 0.79× | — |
| Gemini 3.1 Flash Litebudgetlegacy | $225 | $175 | 0.88× | ▲2 | |
| Gemini 3.5 Flash Litebudget | $225 | $187 | — | — | |
| GPT-5 Minibudgetlegacy | OpenAI | $260 | $222 | — | ▲1 |
| GPT-OSS 120B (Cerebras)budget | Cerebras | $221 | $290 | 2.33× | ▼3 |
| Mistral Medium 3budget | Mistral | $332 | $310 | 0.84× | ▲2 |
| Gemini 2.5 Flashbudgetlegacy | $319 | $274 | — | — | |
| Llama 3.3 70Bbudgetlegacy | Groq | $339 | $328 | 0.81× | ▲1 |
| DeepSeek V4 Probudget | DeepSeek | $270 | $345 | 3.31× | ▼3 |
| GLM-5.1midlegacy | Z.ai | $442 | $442 | — | — |
| Qwen 3.8 30Bmid | Groq | $498 | $498 | — | — |
| Qwen 3.6 27Bmidlegacy | Groq | $498 | $498 | — | — |
| Qwen 3.7 Plusmid | Qwen | $524 | $524 | — | — |
| Amazon Nova Promid | Amazon | $608 | $487 | — | — |
| GPT-5.4 Minimidlegacy | OpenAI | $675 | $562 | — | — |
| Gemini 3.1 Flashmidlegacy | $675 | $562 | — | — | |
| Claude Haiku 4.5mid | Anthropic | $830 | $679 | — | ▲1 |
| o3-Minimidlegacy | OpenAI | $836 | $670 | — | ▲1 |
| Grok 4.3mid | xAI | $775 | $849 | 1.42× | ▼2 |
| Qwen 3.8 Maxmid | Qwen | $1,216 | $1,216 | — | ▲1 |
| Qwen 3.7 Maxmid | Qwen | $1,216 | $1,216 | — | ▲1 |
| Grok-3midlegacy | xAI | $1,240 | $1,240 | — | ▲1 |
| GPT-5midlegacy | OpenAI | $1,300 | $1,111 | — | ▲2 |
| Gemini 3.6 Flashmid | $1,350 | $1,123 | — | ▲2 | |
| Gemini 3.5 Flashmidlegacy | $1,350 | $1,123 | — | ▲2 | |
| Grok-4.20 Reasoningmid | xAI | $1,380 | $1,380 | — | ▲2 |
| Grok-4.20mid | xAI | $1,380 | $1,380 | — | ▲2 |
| Mistral Large 3mid | Mistral | $1,380 | $1,380 | — | ▲2 |
| Gemini 3.1 Promid | $1,800 | $1,187 | 0.63× | ▲4 | |
| GPT-4.1midlegacy | OpenAI | $1,520 | $1,218 | — | ▲1 |
| GPT-5.6 Terramid | OpenAI | $1,800 | $1,498 | — | ▲1 |
| GLM-5.2mid | Z.ai | $980 | $1,864 | 3.87× | ▼12 |
| GPT-4omidlegacy | OpenAI | $1,900 | $1,522 | — | ▲1 |
| GPT-5.4midlegacy | OpenAI | $2,250 | $1,872 | — | ▲1 |
| Claude Sonnet 4.6mid | Anthropic | $2,490 | $2,036 | — | ▲1 |
| Claude Sonnet 4.5midlegacy | Anthropic | $2,490 | $2,036 | — | ▲1 |
| Claude Sonnet 4midlegacy | Anthropic | $2,490 | $2,036 | — | ▲1 |
| GLM 4.7 (Cerebras)mid | Cerebras | $1,273 | $2,533 | 7.55× | ▼14 |
| Claude Opus 4.8mid | Anthropic | $4,150 | $3,324 | 0.96× | — |
| Claude Opus 4.7midlegacy | Anthropic | $4,150 | $3,394 | — | — |
| Claude Opus 4.6midlegacy | Anthropic | $4,150 | $3,394 | — | — |
| Claude Opus 4.5midlegacy | Anthropic | $4,150 | $3,394 | — | — |
| GPT-5.6 Solfrontier | OpenAI | $4,500 | $3,744 | — | — |
| GPT-4 Turbofrontierlegacy | OpenAI | $6,900 | $5,388 | — | — |
| Claude Fable 5frontier | Anthropic | $8,300 | $6,788 | — | — |
| Claude Opus 4.1frontierlegacy | Anthropic | $12,450 | $10,182 | — | — |
| Claude Opus 4frontierlegacy | Anthropic | $12,450 | $10,182 | — | — |
| GPT-5.4 Profrontierlegacy | OpenAI | $27,000 | $22,968 | 1.04× | — |
Prompt caching assumes a 90% saving on the cacheable share of input — a stated modelling assumption, providers publish 75-90% off. See the full formula and coverage disclosure →