What are the typical API costs for AI agents?
Major Providers and Pricing
OpenAI's GPT-4 is one of the more expensive options, at roughly $0.03 per 1,000 tokens for input and $0.06 for output (as of 2025). GPT-3.5 Turbo is much cheaper, around $0.001–$0.002 per 1,000 tokens. Anthropic's Claude models are similarly priced, with Claude 3 Opus around $0.015 per 1,000 input tokens and $0.075 for output.
Google's Gemini offers competitive rates, with Gemini Pro at about $0.00025 per 1,000 characters (roughly $0.001 per 1,000 tokens). Open-source models via providers like Together AI or Anyscale can be even cheaper, sometimes under $0.001 per 1,000 tokens.
- GPT-4: ~$0.03/$0.06 per 1K input/output tokens.
- GPT-3.5 Turbo: ~$0.001–$0.002 per 1K tokens.
- Claude 3 Opus: ~$0.015/$0.075 per 1K tokens.
- Gemini Pro: ~$0.001 per 1K tokens.
- Open-source models: often <$0.001 per 1K tokens.
Estimating Agent Costs
To estimate costs, calculate average tokens per task. A simple Q&A might use 500 tokens, costing $0.015 with GPT-4. A complex task with multiple tool calls could use 10,000 tokens, costing $0.30. Add retries and error handling, which can increase usage by 20–50%.
For budgeting, multiply the cost per task by expected volume. For 1,000 tasks per month at $0.10 each, that's $100. Always monitor actual usage and set alerts to avoid overspending.
- Estimate tokens per task based on complexity.
- Account for retries and tool calls.
- Use cheaper models for non-critical tasks.
- Implement caching to reduce repeated calls.
- Set budget alerts with your provider.
Common mistakes
- Assuming all models cost the same; prices vary significantly.
- Forgetting that output tokens often cost more than input tokens.
- Not factoring in costs for embeddings or other API services.
