Managing AI Compute & API Costs
AI infrastructure can be cheap or catastrophically expensive. The difference is strategy. Every technique in this lesson exists because someone learned the hard way that AI costs don't behave like traditional hosting costs.
What you'll learn
- The real cost breakdown of AI API calls
- Caching strategies that cut costs by 40-70%
- Model selection: when cheaper models are actually better
- Building a tiered architecture that minimizes expensive API calls
Understanding AI Cost Structure
AI API pricing is based on tokens — chunks of text roughly equivalent to 3/4 of a word. You pay for both input tokens (what you send) and output tokens (what the model generates). Output tokens typically cost 3-5x more than input tokens.
A single conversation turn with a large context window can cost $0.05-$0.50. Multiply that by thousands of users and dozens of interactions per user, and you're looking at real money. The organizations that survive are the ones that optimize ruthlessly.
Your system prompt alone might be 2,000 tokens. If that prompt goes with every request, you're paying for it every single time. This is the first place to optimize — make your system prompts as concise as possible.
Caching: Stop Paying Twice
Semantic caching: Before sending a query to an LLM, check if a sufficiently similar query has been answered recently. Use vector similarity to find near-matches. If someone asked "how do I deploy to Vercel?" five minutes ago, the answer to "deploying on Vercel?" is probably the same.
Response caching: For deterministic operations (embeddings, classifications, structured data extraction), cache the result keyed on the input hash. Embeddings for the same text never change — compute them once and store them forever.
Prompt caching: Some providers (including Anthropic) offer prompt caching — if you send the same system prompt repeatedly, you pay full price once and a fraction for subsequent uses. Structure your requests to take advantage of this.
A well-implemented caching layer typically reduces AI API costs by 40-70%. That's not an optimization — it's a survival strategy.
This lesson is for Pro members
Unlock all 300+ lessons across 30 courses with Academy Pro. Founding members get 90% off — forever.
Already a member? Sign in to access your lessons.