Cost Optimization for LLM Systems: Where the Money Actually Goes

LLM costs scale linearly with usage. A system processing 10,000 requests a day at $0.01 per request costs $100 daily — $365 a year. At enterprise scale, that's over $10,000. Cost optimization isn't about cutting corners. It's about spending tokens where they matter. Every token you waste is a token you could have spent on a better answer. Token budgeting The simplest way to control costs is to set limits. Per session, per task, or per day. Strategy 1: Per-Session Budgets Per-session budgets are straightforward: class SessionBudget : def __init__ ( self , budget_tokens : int = 10000 ): self . budget = budget_tokens self . used = 0 def allocate ( self , tokens : int ) -> bool : if self . used + tokens <= self . budget : self . used += tokens return True return False def remaining ( self ) -> int : return self . budget - self . used Strategy 2: Per-Task Budgets Per-task budgets are more useful. Different tasks need different amounts of context: task_budgets : classify : max_tokens : 100 model : qwen2.5-1.5b summarize : max_tokens : 500 model : qwen2.5-7b code_review : max_tokens : 2000 model : qwen2.5-coder-7b reason : max_tokens : 4000 model : qwen2.5-32b Strategy 3: Adaptive Budgets Adaptive budgets adjust based on what actually happens. If classification tasks consistently use 80 tokens, stop allocating 100: class AdaptiveBudget : def __init__ ( self ): self . task_history = {} def allocate ( self , task_type : str ) -> int : if task_type in self . task_history : return int ( self . task_history [ task_type ] * 1.5 ) return 1000 def record ( self , task_type : str , tokens_used : int ): if task_type not in self . task_history : self . task_history [ task_type ] = tokens_used else : self . task_history [ task_type ] = ( 0.9 * self . task_history [ task_type ] + 0.1 * tokens_used ) The exponential moving average (0.9 weight) means recent usage matters more than history. Adjust the weight based on how volatile your workloads are. API vs local inference Local inference