Grok 4 Heavy vs Mixtral 8x22B Instruct v0.3
Grok 4 Heavy (2025) and Mixtral 8x22B Instruct v0.3 (2024) are compact production models from xAI and MistralAI. Grok 4 Heavy ships a 256k-token context window, while Mixtral 8x22B Instruct v0.3 ships a 64K-token context window. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit. It focuses on practical selection signals rather than broad model-family marketing. The goal is to make the tradeoff clear before deeper testing.
Grok 4 Heavy fits 4x more tokens; pick it for long-context work and Mixtral 8x22B Instruct v0.3 for tighter calls.
Specs
| Released | 2025-07-09 | 2024-07-01 |
| Context window | 256k | 64K |
| Parameters | — | 8x22B |
| Architecture | - | mixture of experts |
| License | Proprietary | Apache 2.0 |
| Knowledge cutoff | - | - |
Pricing and availability
| Grok 4 Heavy | Mixtral 8x22B Instruct v0.3 | |
|---|---|---|
| Input price | - | $2/1M tokens |
| Output price | - | $2/1M tokens |
| Providers | - |
Capabilities
| Grok 4 Heavy | Mixtral 8x22B Instruct v0.3 | |
|---|---|---|
| Vision | ||
| Multimodal | ||
| Reasoning | ||
| Function calling | ||
| Tool use | ||
| Structured outputs | ||
| Code execution |
Benchmarks
No shared benchmark rows are currently sourced for this pair.
Deep dive
The capability footprint differs most on multimodal input: Grok 4 Heavy and function calling: Mixtral 8x22B Instruct v0.3. Both models share the core language-model surface, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.
Pricing coverage is uneven: Grok 4 Heavy has no token price sourced yet and Mixtral 8x22B Instruct v0.3 has $2/1M input tokens. Provider availability is 0 tracked routes versus 1. Treat unknown pricing as an integration gap, then verify the route you will actually call before estimating production spend.
Choose Grok 4 Heavy when long-context analysis and larger context windows are central to the workload. Choose Mixtral 8x22B Instruct v0.3 when provider fit and broader provider choice are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship. This keeps the decision grounded in measurable tradeoffs instead of brand-level assumptions. It also helps separate model capability from provider packaging, which can change cost and latency.
FAQ
Which has a larger context window, Grok 4 Heavy or Mixtral 8x22B Instruct v0.3?
Grok 4 Heavy supports 256k tokens, while Mixtral 8x22B Instruct v0.3 supports 64K tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.
Is Grok 4 Heavy or Mixtral 8x22B Instruct v0.3 open source?
Grok 4 Heavy is listed under Proprietary. Mixtral 8x22B Instruct v0.3 is listed under Apache 2.0. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.
Which is better for multimodal input, Grok 4 Heavy or Mixtral 8x22B Instruct v0.3?
Grok 4 Heavy has the clearer documented multimodal input signal in this comparison. If multimodal input is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Which is better for function calling, Grok 4 Heavy or Mixtral 8x22B Instruct v0.3?
Mixtral 8x22B Instruct v0.3 has the clearer documented function calling signal in this comparison. If function calling is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Where can I run Grok 4 Heavy and Mixtral 8x22B Instruct v0.3?
Grok 4 Heavy is available on the tracked providers still being sourced. Mixtral 8x22B Instruct v0.3 is available on Replicate API. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
When should I pick Grok 4 Heavy over Mixtral 8x22B Instruct v0.3?
Grok 4 Heavy fits 4x more tokens; pick it for long-context work and Mixtral 8x22B Instruct v0.3 for tighter calls. If your workload also depends on long-context analysis, start with Grok 4 Heavy; if it depends on provider fit, run the same evaluation with Mixtral 8x22B Instruct v0.3.
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Last reviewed: 2026-04-18. Data sourced from public model cards and provider documentation.