Which is cheaper, Claude Opus 5 or Grok-4 Fast Non-Reasoning?
As of August 20, 2026, Grok-4 Fast Non-Reasoning is 98% cheaper on blended LLM API pricing. Grok-4 Fast Non-Reasoning costs $0.20 per million input tokens and $0.50 per million output tokens ($0.70 blended 1M-in + 1M-out). Claude Opus 5 costs $5.00 / $25.00 per million tokens ($30.00 blended). Sources: https://platform.claude.com/docs/en/about-claude/pricing and https://docs.x.ai/docs/models. The cheapest LLM for your app still depends on how many output tokens you generate.
How much does Claude Opus 5 vs Grok-4 Fast Non-Reasoning cost per million tokens?
Claude Opus 5 Claude API pricing from Anthropic is $5.00 input and $25.00 output per million tokens via Anthropic. Grok-4 Fast Non-Reasoning xAI API pricing is $0.20 input and $0.50 output per million tokens via xAI. Use those four numbers, not ChatGPT Plus or Claude Pro subscription prices, when you are comparing APIs.
Which is better for coding, Claude Opus 5 or Grok-4 Fast Non-Reasoning?
Claude Opus 5 has a published SWE-bench Verified score of 96%. Grok-4 Fast Non-Reasoning does not have that eval on this page yet.
What is the context window for Claude Opus 5 vs Grok-4 Fast Non-Reasoning?
Claude Opus 5 supports a 1M token context window, while Grok-4 Fast Non-Reasoning supports 2M tokens. Grok-4 Fast Non-Reasoning offers a larger context window. Filling a larger window bills more input tokens, so the cheaper-per-million model can still cost more on long documents.
Which model performs better on benchmarks, Claude Opus 5 or Grok-4 Fast Non-Reasoning?
Claude Opus 5 leads on 11 of 11 shared benchmarks versus Grok-4 Fast Non-Reasoning's 0 wins. Check the comparison table for GPQA Diamond, SWE-bench, MMLU, HLE, and the other evals we track. Token price and benchmark score together are the usual LLM comparison, not either number alone.
Is Claude Opus 5 or Grok-4 Fast Non-Reasoning better for production use?
Both Claude Opus 5 and Grok-4 Fast Non-Reasoning are production API models. For cost-sensitive production traffic, Grok-4 Fast Non-Reasoning has better economics on the blended 1M-in + 1M-out scale. For maximum capability, weight the benchmark table for your domain. Many production stacks route cheap models for drafts and a frontier model for the hard turn, which is usually cheaper than sending everything to the expensive API.
Can I switch between Claude Opus 5 and Grok-4 Fast Non-Reasoning in my app?
Yes. Call Claude Opus 5 through Anthropic and Grok-4 Fast Non-Reasoning through xAI with separate API keys, or through a gateway that already wraps both. Keep prompts in tokens, not characters, when you estimate the invoice. AnotherWrapper templates can swap providers without rewriting auth and billing.
How accurate is this Claude Opus 5 vs Grok-4 Fast Non-Reasoning pricing data?
List rates are the latest published Claude API pricing from Anthropic and xAI API pricing, quoted per million tokens. Official rate sheets: https://platform.claude.com/docs/en/about-claude/pricing and https://docs.x.ai/docs/models. Prompt caching, batch APIs, and committed-use discounts can change the invoice. Benchmark scores are from official publications and independent evals, updated as new numbers land.
What is the output token limit for Claude Opus 5 and Grok-4 Fast Non-Reasoning?
Claude Opus 5 supports up to 128K output tokens per request, while Grok-4 Fast Non-Reasoning supports up to 30K output tokens. Output tokens are usually the expensive half of API pricing, so a higher max output cap is a capability, not a discount.
Which model has better throughput, Claude Opus 5 or Grok-4 Fast Non-Reasoning?
Claude Opus 5 runs at approximately 3.437096666269855 tokens/second while Grok-4 Fast Non-Reasoning runs at 90 tokens/second. Grok-4 Fast Non-Reasoning is faster in raw throughput. Throughput (tokens per second) and time-to-first-token are why two models with the same per-million-token price can still feel different in chat and agents.
How do I switch the models in this Claude Opus 5 vs Grok-4 Fast Non-Reasoning comparison?
Use the model pickers at the top of this LLM comparison. Search any model in the index and the URL updates. Open Claude Opus 5 or Grok-4 Fast Non-Reasoning from the sidebar for the single-model API pricing page, or go back to the LLM pricing table to sort by cheapest blended cost.
