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Claude Opus 4.5 vs Grok 3 Fast

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Anthropic · 200k context  |  xAI · 128k context

Pricing Comparison

MetricClaude Opus 4.5Grok 3 Fast
Input / 1M tokens$15$5
Output / 1M tokens$75$25
Cached input / 1M$1.5—
Context window200k128k
ProviderAnthropicxAI

Cost Calculator

💰 Grok 3 Fast saves $10,500.00/month (67% cheaper)
AClaude Opus 4.5
Per request$0.0525
Daily$525.00
Monthly$15,750.00
Yearly$191,625.00
XGrok 3 FastCHEAPER
Per request$0.0175
Daily$175.00
Monthly$5,250.00
Yearly$63,875.00
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Choose Claude Opus 4.5 when…

  • ✓ Larger context window (200k vs 128k) — better for long documents
  • ✓ Supports prompt caching — save up to 90% on repeated prompts
  • ✓ Optimized for: Complex reasoning & coding
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Choose Grok 3 Fast when…

  • ✓ Cheaper for RAG & document retrieval (lower input cost)
  • ✓ 67% cheaper per input token
  • ✓ Cheaper for generation-heavy workloads (lower output cost)
  • ✓ Optimized for: Low-latency flagship tasks

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