September 14, 2026
A pre-build framework for forecasting chatbot API costs: per-turn token budgets, how conversation history compounds cost, and the mistakes that blow up estimates by 5-10x.
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NumStack Blog
Articles on AI costs, model selection, optimization, and ROI analysis.
September 14, 2026
How LLM API pricing actually works: why output costs more than input, what reasoning tokens are, and how caching and batch discounts change the math.
Read Article →How to Pick the Cheapest Model That Is Still Good Enough
Model SelectionSeptember 14, 2026
A framework for choosing the cheapest model that meets your quality bar: task-tiering, cost-per-correct-answer math, and cascading model routing.
Read Article →September 14, 2026
Fine-tuning is a fixed cost traded for a smaller recurring one. The real cost anatomy and a break-even model with worked numbers.
Read Article →September 14, 2026
Why an agent task costs far more than "steps times one API call": how tool results compound context, and how to cap runaway agent costs.
Read Article →September 14, 2026
What actually drives vector DB cost: storage math, query pricing, quantization, and a provider comparison of Pinecone, Weaviate, Qdrant, Supabase, and Chroma.
Read Article →September 14, 2026
Why latency and throughput are different constraints, what actually caps concurrency, and a worked capacity-planning walkthrough.
Read Article →September 14, 2026
A tactical playbook for reducing token costs: trimming system prompts, capping output, compressing history, and caching — with worked before/after numbers.
Read Article →September 14, 2026
GPU-hours, not tokens, drive this bill. The cost formula, why LoRA/QLoRA changes the math, and the hidden costs that blow up a training budget.
Read Article →June 3, 2026
Learn how to forecast and optimize AI costs before they surprise you. From token counting to model selection, here's the complete guide.
Read Article →September 14, 2026
A model-by-model price comparison of the current OpenAI and Anthropic lineups, with worked cost examples and when each provider's tiers make sense by workload shape.
Read Article →June 3, 2026
Simple framework for deciding if an AI chatbot makes financial sense for your business. Cost per conversation, payback period, and ROI calculations.
Read Article →Turn any of this into a real number
Every guide above links to a calculator built for that exact decision — token pricing, model selection, agents, fine-tuning, vector DBs, and infrastructure sizing.
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