AI model comparison · Free
Compare Grok 4 Fast and Runway Gen4 across capabilities, strengths, limitations, pricing availability, and practical prompt workflows. Use it for free on Unify.
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Grok 4 Fast is provided by xAI and emphasizes fast reasoning and low cost. Runway Gen4, from Runway, emphasizes professional quality and creative control. The stronger option depends on the input, output constraints, and review standard.
Run the same prompt, source context, output format, and acceptance criteria through both models. Score accuracy, instruction following, edit time, latency, and current cost separately. Repeat the test on several representative tasks before standardizing on either model.
| Criteria | Primary | Comparison |
|---|---|---|
| Provider | xAI | Runway |
| Category | chat | image |
| Top strength | Fast reasoning | Professional quality |
| Pricing | Check the provider or Unify workspace for current pricing. | Check the provider or Unify workspace for current pricing. |
| Context | Not verified | Not verified |
Act as an expert chat assistant. Produce a clear, production-ready result for [goal], using [constraints] and [audience].
Act as an expert image assistant. Produce a clear, production-ready result for [goal], using [constraints] and [audience].
Compare Grok 4 Fast and Runway Gen4 across capabilities, strengths, limitations, pricing availability, and practical prompt workflows.
Results can vary with prompt specificity and chat task complexity. Results can vary with prompt specificity and image task complexity.
Yes. Use the comparison links on this page and test identical inputs before selecting a model.
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