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Guides for AI cost planning

Reusable guides and tutorials that connect to CentsPerToken calculators—add articles in the learn registry without changing page templates.

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25 pieces covering budgets, routing, and core concepts.

conceptsInput vs output tokens — a simple guide

Why output tokens often dominate the bill, and how to estimate both sides before you call an API.

conceptsWhy tool-calling agents cost more than single-shot chat

How growing context, tool-result tokens, and multi-turn loops drive agent API bills—and how to estimate them.

guidesHow prompt caching reduces LLM API costs

Separate stable prefixes from dynamic tokens, estimate hit rate, and account for cache-write fees when planning spend.

guidesChoosing models by latency vs API cost

How to set a latency SLO, compare planning p50 latency with list prices, and avoid overpaying for speed you do not need.

tutorialsHow to pick the cheapest model without breaking quality

Use task presets, capability floors, and evals so cost routing stays safe in production.

guidesUnit economics for SaaS AI features

Connect token costs, adoption, and pricing so AI features stay within a healthy COGS band.

conceptsAPI resale margin: cost vs what you charge

How to price AI wrappers and products so provider COGS, payment fees, and overhead still leave healthy margin.

guidesConvert USD AI API bills to GBP, EUR, AUD, and CAD

How UK, EU, Australian, and Canadian teams should budget OpenAI and Anthropic invoices that arrive in dollars.

tutorialsHow to analyze an LLM usage CSV without uploading it

Export model and token columns, match them to list prices in the browser, and spot invoice variance.

guidesWhen self-hosted LLMs beat API pricing

Compare GPU-hour economics to hosted token prices, and know which assumptions flip the decision.

conceptsWhy bigger context windows cost more

How 8K vs 128K vs 1M prompts change token bills—and when caching or retrieval beats stuffing everything in.

guidesHow API rate limits shape LLM cost and capacity

RPM, TPM, concurrency, and daily caps decide your real ceiling—often before list price does.

guidesAllocate AI API budget across team seats

Use role weights and hard caps so a few power users do not consume the whole monthly AI pool.

conceptsHow much do 1 million tokens cost?

A plain explanation of per-1M input and output prices—and why your real 1M-token bill depends on the mix.

conceptsWhy retries inflate AI API cost

How rate limits, timeouts, and partial billing turn a “successful job” budget into extra attempts and spend.

guidesHow to estimate PDF and document ingestion cost

Turn pages into tokens, account for chunk overlap, and decide when an LLM extract pass is worth the spend.

conceptsDoes streaming change LLM API cost?

Why streamed and buffered responses usually share list prices—and when early cancel or wait economics tip the comparison.

guidesHow to price A/B and cascade model routing

Estimate LLM spend when you split traffic or escalate hard cases from a cheap primary to a premium model.

guidesHow to estimate multi-provider failover cost

Price an availability path: primary success rate, failed-attempt billing, and secondary spend during blips or outages.

guidesHow to estimate LLM-as-judge eval cost

Break eval spend into candidate generation and judge scoring—and see why rubric dimensions multiply the bill.

guidesHow to estimate synthetic data generation cost

Price generate → critique → filter pipelines and understand why accept rate drives over-generation spend.

guidesWhen does a RAG re-ranker pay for itself?

LLM rerank adds calls, but feeding top-N instead of top-K into the generator can cut context tokens enough to win overall.

guidesHow to estimate LLM API costs before you ship

A practical framework for turning traffic assumptions into monthly OpenAI, Anthropic, and Google API spend.

tutorialsBatch API vs realtime: when to switch

Learn how to compare batch and realtime pricing for the same token workload with CentsPerToken.

conceptsWhat is a token in LLM APIs?

A plain-language explanation of tokens and why they drive AI API bills.