# "I 4×'d My Prompt and Doubled My Tokens": 8 Most Common Prompt Cost Mistakes in Production

> Source: https://sukruyusufkaya.com/en/learn/token-ekonomisi/prompt-maliyeti-hatalari-8-yaygin-pattern
> Updated: 2026-05-14T14:44:12.659Z
> Category: Token Ekonomisi & LLM Cost Optimization
> Module: Module 5: The Cost Dimension of Prompt Engineering
**TLDR:** Prompt engineering is usually written from a quality lens — but every extra token directly hits your bill. This lesson covers the 8 most common mistakes in production, with real prompt examples and before/after token counts.