AI Coding Agent & Multi-Turn Tool Call Cost Calculator
Calculate multi-turn context accumulation and file inspection API token costs for autonomous AI coding agents like Claude Code, Cline, and Roo Code.
Describe Your Workload
= 15,000 requests a month (30 days)
System prompt + chat history + retrieved documents + the user's message.
Count too: they bill as output.
Rule of thumb for English: is roughly 750 words.
With , the repeated start of each prompt is billed at the cheaper cache-read rate.
Claude Sonnet 5.5
- Input: 30M tokens @ $2/M
- $60.00
- Cached input: 90M tokens @ $0.1/M
- $9.00
- Output: 18M tokens @ $10/M
- $180.00
- Total per month
- $249.00
Cost = tokens ÷ 1,000,000 × price per 1M, summed for input, cached input and output
Cheapest mid-tier model for this workload: Mistral Large 4 at $65.10/month (74% less). Cheapest overall: DeepSeek V4.1 Flash at $11.97/month. Cheaper models can be weaker, so test them on your own prompts before switching.
This Workload on Every Model
120M input and 18M output tokens a month at real-time prices. Cheapest first; tap a model to load it above.
| Model | Tier | Input / 1M | Cached / 1M | Output / 1M | Context | Monthly cost | vs Claude Sonnet 5.5 |
|---|---|---|---|---|---|---|---|
| DeepSeek | Budget | $0.045 | $0.018 | $0.5 | 1M | $11.97 | -95% |
| Anthropic | Budget | $0.1 | $0.01 | $0.5 | 1M | $12.90 | -95% |
| OpenAI | Budget | $0.1 | $0.01 | $0.5 | 1.1M | $12.90 | -95% |
| Alibaba Qwen | Budget | $0.15 | $0.016 | $0.47 | 1M | $14.40 | -94% |
| Budget | $0.25 | $0.025 | $1.5 | 1M | $36.75 | -85% | |
| Meta (open weights) | Budget | $0.35 | $0.17 | $1 | 524.3K | $43.80 | -82% |
| Mistral | Mid | $0.7 | $0.07 | $2.1 | 1M | $65.10 | -74% |
| DeepSeek | Mid | $0.103 | $0.098 | $4.11 | 1M | $85.89 | -66% |
| Mid | $0.825 | $0.0825 | $4.125 | 1M | $106.43 | -57% | |
| OpenAI | Mid | $1 | $0.05 | $5 | 1.1M | $124.50 | -50% |
| xAI | Flagship | $2 | $0.5 | $6 | 500K | $213.00 | -14% |
| Anthropic | Mid | $2 | $0.1 | $10 | 1M | $249.00 | selected |
| Flagship | $2 | $0.1 | $10 | 1M | $249.00 | 0% | |
| OpenAI | Mid | $2 | $0.1 | $10 | 1.1M | $249.00 | 0% |
| Anthropic | Flagship | $4 | $0.2 | $20 | 1M | $498.00 | +100% |
| Anthropic | Flagship | $10 | $0.25 | $50 | 1M | $1,222.50 | +391% |
| OpenAI | Flagship | $10 | $1 | $50 | 1.1M | $1,290.00 | +418% |
Prices are the per-token rates OpenRouter listed on 5 Nov 2026. Buying direct from a provider can be priced differently, and some providers charge more for very long prompts, so check the provider's pricing page before you commit a budget. Cache-write charges (paid the first time a prefix is cached) are not included; with a high cache share they add little. A month is 30 days.
Notes for This Preset
A coding agent that makes 500 model calls a day (15,000 requests/month), using example inputs of 8,000 input tokens (file context, terminal output and tool definitions) and 1,200 output tokens per call, costs $249.00/month ($16.60 per 1,000 calls) on Claude Sonnet 5.5 with 75% of the input served from cache, at the OpenRouter prices of 5 November 2026. Without caching the same workload costs $420.00/month. Output tokens cost 5 times as much as input on this model ($10.00 vs $2.00 per 1M), so shorter answers lower the bill too. Real agent traffic varies a lot: replace the example token counts with your own.
How can I lower the API bill for this workload?
Three levers, in order of effort: cache the repeated start of the prompt (system prompt, documents, tool definitions), move work that can wait to the Batch API, and test a cheaper model on your own prompts. Shorter answers help too, because output tokens cost several times more than input tokens.
Building an AI Chatbot, Agent or RAG App?
Vsurge Media builds production AI assistants, RAG search and automation for businesses, and helps keep the monthly API bill under control.