TL;DR: I built a free calculator that models the true cost of AI autonomous agents vs. human VAs — and the results surprised me. If you're building with LLM APIs in 2026, you've probably celebrated how cheap inference has become. GPT-4o Mini at $0.15/1M tokens. DeepSeek V3 at $0.14/1M tokens. It feels almost free. Until you run an autonomous agent loop. Then the math breaks in ways nobody warned you about. The Problem: Context Windows Are Cost Multipliers Step 1: 1,500 tokens When AI Wins vs. When Humans Win The core logic: javascript const totalInTokens = (steps * (steps + 1) / 2) * avgTokensPerStep; const costPerTask = (totalInTokens / 1_000_000) * model.inputPrice; ai, webdev, javascript, programming.