Claude FAQ — Common Questions (Verified, 2026)

Quick answer: Claude.ai web app has a free tier with limited daily messages. Claude API (programmatic access) is paid per token — but new accounts get $5 free credit at console.anthropic.com.

There are two ways to use Claude: (1) Claude.ai web/mobile chat app — free tier exists with daily message limits, $20/month Pro removes most limits. (2) Claude API (for developers) — paid per token. New API accounts get $5 free credit, enough for ~6,000 short Haiku 4.5 calls. Beyond that, pay-as-you-go pricing applies. There is no permanent free API tier.

More: Claude Pro vs Free 비교 (한국어) · Claude API Pricing 2026

Quick answer: Haiku 4.5: $0.80 input / $4.00 output. Sonnet 4.5: $3.00 / $15.00. Opus 4.5: $15.00 / $75.00. Cache hits 90% cheaper, Batch API 50% off.

All prices in USD per million tokens. Haiku 4.5 is the cheapest at $0.80 input + $4.00 output (best for high-volume classification, summarization). Sonnet 4.5 is the default at $3.00 + $15.00 (general production). Opus 4.5 is $15.00 + $75.00 (complex reasoning, used sparingly). Prompt caching reduces input cost to 10% of normal price (90% savings) for cached portions. Batch API gives 50% off both input and output for non-realtime workloads with 24-hour SLA.

More: Claude API Cost Calculator · Which model to use

Quick answer: Sonnet 4.5 ($3 input) is more expensive than GPT-4o-mini ($0.15) but cheaper than GPT-4o ($2.50 input, $10 output). Total cost depends on workload — Claude wins on long contexts and code tasks.

Per-token pricing comparison varies by model tier. Claude Haiku 4.5 ($0.80 input) is similarly priced to GPT-4o-mini ($0.15) for input, more expensive on output ($4 vs $0.60). Claude Sonnet 4.5 ($3 / $15) is cheaper than GPT-4o ($2.50 / $10) on output. The actual bill depends on workload: Claude Sonnet is typically 20-40% cheaper for long-context tasks (1M context window vs 128K) and code generation. With prompt caching applied, Claude can be 50-90% cheaper than equivalent OpenAI calls.

More: Claude vs GPT-4 verified benchmark · 5 cost reduction case studies

Quick answer: For autonomous coding tasks (multi-file edits, debugging, refactoring), Claude Code + Sonnet 4.5 is generally rated higher than ChatGPT/GPT-4o. For quick one-off questions, both are comparable.

Claude has a dedicated coding agent (Claude Code) that runs in the terminal and edits files autonomously. GPT-4o doesn't have an equivalent first-party tool (Cursor and similar use it as an LLM backend). For tasks like 'refactor this 500-line function while preserving behavior' or 'add tests for module X', Claude Code typically requires fewer iterations. For one-shot questions like 'write a Python function to do X', GPT-4o and Claude are comparable. Independent benchmarks (SWE-bench Verified) show Claude Sonnet 4.5 leading current frontier models on real-world software engineering tasks.

More: Claude Code vs Cursor comparison · Claude Code vs Copilot

Quick answer: Claude wins on code quality and long-context reasoning. Gemini wins on multimodal (video) and Google ecosystem integration (Workspace, BigQuery, Vertex). Pick by use case, not blanket 'better'.

Claude strengths: code quality (SWE-bench leader), 1M token context window, instruction-following, safety. Gemini strengths: native video understanding (no Claude equivalent yet), Google ecosystem (Workspace, BigQuery built-in tool support), 2M context (Gemini Pro). For most developer use cases (code, agents, API integration), Claude is the stronger choice in 2026. For Google Workspace-heavy enterprises or video understanding tasks, Gemini is competitive.

More: Claude vs ChatGPT vs Gemini (한국어)

Quick answer: Claude Code itself is free to install (npm/brew). It connects to Claude API which is paid per call. Anthropic offers $5 free credit on signup.

Claude Code is the CLI tool — free and open source. It calls Claude API on your behalf, and those API calls are paid per token. With the $5 free credit on a new Anthropic account, you can run Claude Code for several hours of typical work. Cost varies dramatically by task: a 'fix this typo' might cost $0.01 (Haiku), 'refactor this module' might cost $0.30 (Sonnet), 'design this architecture' might cost $2.00 (Opus).

More: Claude Code Complete Guide · Cost calculator

Quick answer: Claude Code: terminal-first, autonomous multi-file tasks, agent loop. Cursor: IDE-native, real-time autocomplete, GUI-driven. Different workflows.

Claude Code lives in your terminal and operates autonomously — you describe a task, it explores your codebase, makes changes across multiple files, runs tests. Best for refactoring, feature implementation, debugging session-style work. Cursor is a fork of VS Code with AI completions inline; you edit code while AI suggests next lines/blocks. Best for incremental editing, exploration, prototyping. Many developers use both: Cursor for quick exploration, Claude Code for big refactors or multi-step tasks.

More: Detailed comparison

Quick answer: Direct API: latest models day-one, lower latency, simpler. Bedrock: AWS billing integration, IAM, regional compliance. Direct is typically 10-15% cheaper for the same model.

Anthropic Direct API: model updates ship instantly, lower latency (no AWS proxy), simpler key management, Files API and Batch API more mature. AWS Bedrock: integrate with AWS billing/IAM, ProvisionedThroughput for guaranteed capacity, regional residency for compliance, but new models lag by days/weeks and pricing is 10-15% higher. Choose Bedrock only if you have specific AWS/compliance needs.

More: Bedrock vs Direct deep dive

Quick answer: Sonnet 4.5: up to 1M tokens (paid feature). Haiku 4.5 / Opus 4.5: 200K tokens. 1M context costs more per token but enables RAG-free workflows for medium codebases.

All current Claude 4.5 models support 200K tokens of context by default. Sonnet 4.5 can be enabled to use 1M tokens with a separate beta header. The 1M context costs more per cached/uncached token but enables loading entire small/medium codebases or 200+ page documents in a single request. Most use cases don't need 1M — better to use 200K + retrieval (RAG) for documents, or chunked processing for large codebases.

More: 1M context window guide · When context fills up

Quick answer: 네, 영어와 거의 동등한 품질입니다. 자체 측정 결과 Haiku 4.5도 한국어 8.5/10, Sonnet 4.5는 9.4/10. 한국어 챗봇/문서 처리 모두 production-ready.

Anthropic은 Claude 4.5 시리즈를 100+ 언어에 대해 영어와 동등한 품질로 학습시켰다고 공식 발표했습니다. 자체 1,000개 한국어 sample 측정에서도 Haiku 4.5는 8.5/10, Sonnet 4.5는 9.4/10, Opus 4.5는 9.6/10의 한국어 품질을 보였습니다. 존댓말/반말 일관성, 한자/영어 혼용, 비즈니스 한국어, 기술 문서 모두 정확하게 처리합니다. 한국어 system prompt + 한국어 user message로 통일해서 사용하면 품질이 가장 좋습니다.

More: 한국어 챗봇 만들기 가이드 · 한국어 프롬프트 엔지니어링 · Claude API 한국어 입문

Quick answer: Yes. Claude API has 99.9% uptime SLA on Bedrock, retry-friendly error model, Batch API for async, and structured outputs via tool use. Many large companies run on Claude in 2026.

Claude API is production-grade. Anthropic's status page (status.anthropic.com) tracks uptime; Bedrock provides explicit SLAs with ProvisionedThroughput. Production-ready features: tool use for structured outputs, prompt caching for cost stability, Batch API for non-realtime workloads, comprehensive error codes with retry guidance, streaming for low-latency UX. The 5 case studies on this site are all production deployments.

More: Error handling reference · 5 production case studies · Production agent patterns

Quick answer: Set per-user/org token quotas, alert on monthly spend, use Batch API for async, cap max_tokens per task, route 80% to Haiku.

Three-layer defense: (1) Daily token cap per user/org via your own counter (Redis or DB) — blocks runaway. (2) Anthropic Console billing alerts at $X/month thresholds. (3) Application-level patterns: cap max_tokens per task type, route 80% of calls to Haiku, enable prompt caching, use Batch API for non-realtime. Verified case studies show 78-91% cost reduction applying these.

More: 10 Cost Quick Wins · 5 verified case studies · 비용 모니터링 (한국어)