Claude Mythos 5 vs Grok-4.1 Fast Reasoning

    Comparison

    As of August 20, 2026, Grok-4.1 Fast Reasoning is 99% cheaper per million tokens than Claude Mythos 5. Claude Mythos 5 is $10.00 / $50.00 per million input/output tokens versus Grok-4.1 Fast Reasoning at $0.20 / $0.50. Sources: https://platform.claude.com/docs/en/about-claude/pricing and https://docs.x.ai/docs/models

    Sources: Anthropic Claude API pricing (https://platform.claude.com/docs/en/about-claude/pricing); xAI API pricing (https://docs.x.ai/docs/models)

    Claude Mythos 5

    Anthropic

    $60.00blended / 1M

    Input

    $10.00

    Output

    $50.00

    1M ctx|Proprietary
    99%
    cheaper
    Better value

    Grok-4.1 Fast Reasoning

    xAI

    $0.70blended / 1M

    Input

    $0.20

    Output

    $0.50

    2M ctx|Proprietary
    Save $59.30 per million tokens by choosing Grok-4.1 Fast Reasoning over Claude Mythos 5.

    Claude Mythos 5 vs Grok-4.1 Fast Reasoning comparison

    Token pricing, specs, and benchmarks side by side

    Metric
    Claude Mythos 5
    Grok-4.1 Fast Reasoning
    Provider
    Provider
    Anthropic
    xAI
    License
    Proprietary
    Proprietary
    Release Date
    2026-06-09
    2025-11-17
    Pricing (per 1M tokens)
    Input Price+4900%
    $10.00
    $0.20
    Output Price+9900%
    $50.00
    $0.50
    Blended (1M + 1M)
    $60.00
    $0.70
    Model Details
    Context Window
    1M
    2M
    Max Output Tokens
    128K
    30K
    Knowledge Cutoff
    N/A
    N/A
    Throughput
    N/A
    90 tok/s
    Benchmarks
    94.6%
    94.6%
    84.3%
    85%
    61.7%
    79%
    91.9%
    69.6%
    72.7%
    66.0%
    83.1%
    1932
    3.1%
    28.1%
    92.1%
    78.7%
    89.5%
    84.2%
    67.1%
    31.3%
    Swe Bench Multimodal Internal
    59%
    73.1%
    Benchmark Wins
    Claude Mythos 5 2|0 Grok-4.1 Fast Reasoning

    Verdict

    Claude Mythos 5 vs Grok-4.1 Fast Reasoning: the bottom line

    Grok-4.1 Fast Reasoning offers significantly lower pricing, while Claude Mythos 5 leads on benchmark performance. Your choice depends on whether cost efficiency or raw capability matters more for your use case.

    Claude Mythos 5 vs Grok-4.1 Fast Reasoning FAQ

    Which is cheaper, Claude Mythos 5 or Grok-4.1 Fast Reasoning?

    As of August 20, 2026, Grok-4.1 Fast Reasoning is 99% cheaper on blended LLM API pricing. Grok-4.1 Fast Reasoning costs $0.20 per million input tokens and $0.50 per million output tokens ($0.70 blended 1M-in + 1M-out). Claude Mythos 5 costs $10.00 / $50.00 per million tokens ($60.00 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 Mythos 5 vs Grok-4.1 Fast Reasoning cost per million tokens?

    Claude Mythos 5 Claude API pricing from Anthropic is $10.00 input and $50.00 output per million tokens via Anthropic. Grok-4.1 Fast 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 Mythos 5 or Grok-4.1 Fast Reasoning?

    Claude Mythos 5 leads on SWE-bench Verified: Claude Mythos 5 at 95.5% vs Grok-4.1 Fast Reasoning at 41.4%. SWE-bench measures real GitHub fixes; LiveCodeBench measures contest programming.

    What is the context window for Claude Mythos 5 vs Grok-4.1 Fast Reasoning?

    Claude Mythos 5 supports a 1M token context window, while Grok-4.1 Fast Reasoning supports 2M tokens. Grok-4.1 Fast 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 Mythos 5 or Grok-4.1 Fast Reasoning?

    Claude Mythos 5 leads on 2 of 2 shared benchmarks versus Grok-4.1 Fast 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 Mythos 5 or Grok-4.1 Fast Reasoning better for production use?

    Both Claude Mythos 5 and Grok-4.1 Fast Reasoning are production API models. For cost-sensitive production traffic, Grok-4.1 Fast 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 Mythos 5 and Grok-4.1 Fast Reasoning in my app?

    Yes. Call Claude Mythos 5 through Anthropic and Grok-4.1 Fast 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 Mythos 5 vs Grok-4.1 Fast 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 Mythos 5 and Grok-4.1 Fast Reasoning?

    Claude Mythos 5 supports up to 128K output tokens per request, while Grok-4.1 Fast 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 Mythos 5 or Grok-4.1 Fast Reasoning?

    Grok-4.1 Fast Reasoning has a measured throughput of approximately 90 tokens/second. Throughput data for Claude Mythos 5 is not yet available. 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 Mythos 5 vs Grok-4.1 Fast 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 Mythos 5 or Grok-4.1 Fast 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.

    Claude Mythos 5 vs Grok-4.1 Fast Reasoning pricing

    This comparison covers API pricing, context window, throughput, and benchmark scores. Claude Mythos 5 costs $10.00/M input and $50.00/M output. Grok-4.1 Fast Reasoning costs $0.20/M input and $0.50/M output.

    Rank both on the LLM leaderboard, SWE-bench, and Humanity's Last Exam.

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