LLM Reference

Grok 4.20 vs Mistral Large 3 675B Instruct

Grok 4.20 (2026) and Mistral Large 3 675B Instruct (2025) are frontier reasoning models from xAI and MistralAI. Grok 4.20 ships a 1m-token context window, while Mistral Large 3 675B Instruct ships a 128k-token context window. On Google-Proof Q&A, Grok 4.20 leads by 44.1 pts. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.

Mistral Large 3 675B Instruct is ~150% cheaper at $0.50/1M; pay for Grok 4.20 only for reasoning depth.

Decision scorecard

Local evidence first
SignalGrok 4.20Mistral Large 3 675B Instruct
Best forreasoning-heavy apps, multimodal apps, and tool-calling agentsmultimodal apps and provider-routed production
Decision fitCoding, RAG, and AgentsCoding, RAG, and Agents
Context window1m128k
Cheapest output$2.50/1M tokens$1.50/1M tokens
Provider routes2 tracked5 tracked
Shared benchmarksGoogle-Proof Q&A leader2 rows

Decision tradeoffs

Choose Grok 4.20 when...
  • Grok 4.20 holds a shared-benchmark lead on Google-Proof Q&A, ahead by 44.1 points.
  • Grok 4.20 has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • Grok 4.20 uniquely exposes Reasoning, Function calling, and Tool use in local model data.
  • Local decision data tags Grok 4.20 for Coding, RAG, and Agents.
Choose Mistral Large 3 675B Instruct when...
  • Mistral Large 3 675B Instruct has the lower cheapest tracked output price at $1.50/1M tokens.
  • Mistral Large 3 675B Instruct has broader tracked provider coverage for fallback and procurement flexibility.
  • Local decision data tags Mistral Large 3 675B Instruct for Coding, RAG, and Agents.

Monthly cost at traffic

Estimate token spend from the cheapest tracked input and output route or tier on this page.

Lower estimate Mistral Large 3 675B Instruct

Grok 4.20

$1,625

Cheapest tracked route/tier: xAI Console

Mistral Large 3 675B Instruct

$775

Cheapest tracked route/tier: AWS Bedrock

Estimated monthly gap: $850. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.

Switch friction

Grok 4.20 -> Mistral Large 3 675B Instruct
  • No overlapping tracked provider route is sourced for Grok 4.20 and Mistral Large 3 675B Instruct; plan for SDK, billing, or endpoint changes.
  • Mistral Large 3 675B Instruct is $1/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
  • Check replacement coverage for Reasoning, Function calling, and Tool use before moving production traffic.
Mistral Large 3 675B Instruct -> Grok 4.20
  • No overlapping tracked provider route is sourced for Mistral Large 3 675B Instruct and Grok 4.20; plan for SDK, billing, or endpoint changes.
  • Grok 4.20 is $1/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
  • Grok 4.20 adds Reasoning, Function calling, and Tool use in local capability data.

Specs

Specification
Released2026-02-172025-12-01
Context window1m128k
Parameters675B
Architecture-decoder only
LicenseProprietaryMistral License
OpennessProprietaryOpen weights
Commercial useCommercial use with conditionsNon-commercial only
Knowledge cutoff2024-112024-11

Pricing and availability

Pricing attributeGrok 4.20Mistral Large 3 675B Instruct
Input price$1.25/1M tokens$0.50/1M tokens
Output price$2.50/1M tokens$1.50/1M tokens
Providers

Capabilities

CapabilityGrok 4.20Mistral Large 3 675B Instruct
VisionYesYes
MultimodalYesYes
ReasoningYesNo
Function callingYesNo
Tool useYesNo
Structured outputsYesYes
Code executionNoNo
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

BenchmarkGrok 4.20Mistral Large 3 675B Instruct
Google-Proof Q&A88.043.9
τ-bench78.970.2

Deep dive

On shared benchmark coverage, Google-Proof Q&A has Grok 4.20 at 88 and Mistral Large 3 675B Instruct at 43.9, with Grok 4.20 ahead by 44.1 points; τ-bench has Grok 4.20 at 78.9 and Mistral Large 3 675B Instruct at 70.2, with Grok 4.20 ahead by 8.7 points. The largest visible gap is 44.1 points on Google-Proof Q&A, which matters most when that benchmark mirrors your workload. Treat isolated benchmark wins as directional, because provider routing, prompt style, and tool access can move real application results.

The capability footprint differs most on reasoning mode: Grok 4.20, function calling: Grok 4.20, and tool use: Grok 4.20. Both models share vision, multimodal input, and structured outputs, 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.

For cost, Grok 4.20 lists $1.25/1M input and $2.50/1M output tokens on the cheapest tracked provider, while Mistral Large 3 675B Instruct lists $0.50/1M input and $1.50/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts Mistral Large 3 675B Instruct lower by about $0.83 per million blended tokens. Availability is 2 providers versus 5, so concentration risk also matters.

Choose Grok 4.20 when reasoning depth and larger context windows are central to the workload. Choose Mistral Large 3 675B Instruct when vision-heavy evaluation, lower input-token cost, 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.

FAQ

Which has a larger context window, Grok 4.20 or Mistral Large 3 675B Instruct?

Grok 4.20 supports 1m tokens, while Mistral Large 3 675B Instruct supports 128k tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.

Which is cheaper, Grok 4.20 or Mistral Large 3 675B Instruct?

Mistral Large 3 675B Instruct is cheaper on tracked token pricing. Grok 4.20 costs $1.25/1M input and $2.50/1M output tokens. Mistral Large 3 675B Instruct costs $0.50/1M input and $1.50/1M output tokens. Provider discounts or batch pricing can still change the final bill.

Is Grok 4.20 or Mistral Large 3 675B Instruct open source?

Grok 4.20 is listed under Proprietary. Mistral Large 3 675B Instruct is listed under Mistral License. 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 vision, Grok 4.20 or Mistral Large 3 675B Instruct?

Both Grok 4.20 and Mistral Large 3 675B Instruct expose vision. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface.

Which is better for multimodal input, Grok 4.20 or Mistral Large 3 675B Instruct?

Both Grok 4.20 and Mistral Large 3 675B Instruct expose multimodal input. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface.

Where can I run Grok 4.20 and Mistral Large 3 675B Instruct?

Grok 4.20 is available on xAI Console and OpenRouter. Mistral Large 3 675B Instruct is available on AWS Bedrock, NVIDIA NIM, Mistral AI Studio, Microsoft Foundry, and Vercel AI Gateway. Provider coverage can affect latency, region availability, compliance posture, and fallback options.

Continue comparing

Last reviewed: 2026-06-04. Data sourced from public model cards and provider documentation.