LLM Reference

Codex 1 vs Mistral Medium 3 Instruct

Codex 1 (2025) and Mistral Medium 3 Instruct (2025) compare a coding-specialized model against a standalone API model. Codex 1 ships a 192k-token context window, while Mistral Medium 3 Instruct ships a 128k-token context window. This page treats the result as workflow and deployment fit, not a universal model winner.

Treat this as a product-type comparison: Codex 1 is coding-specialized model, while Mistral Medium 3 Instruct is standalone API model. Choose based on workflow fit before reading any benchmark or price row as decisive.

Decision scorecard

Local evidence first
SignalCodex 1Mistral Medium 3 Instruct
Product typeCoding-specialized modelStandalone API model
Best forcustom coding agents and code generationmultimodal apps and provider-routed production
Decision fitCoding, Agents, and Long contextLong context and Vision
Context window192k128k
Cheapest output-$2/1M tokens
Provider routes0 tracked2 tracked
Shared benchmarks0 shared0 shared

Decision tradeoffs

Choose Codex 1 when...
  • Codex 1 has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • Codex 1 uniquely exposes Reasoning and Code execution in local model data.
  • Local decision data tags Codex 1 for Coding, Agents, and Long context.
Choose Mistral Medium 3 Instruct when...
  • Mistral Medium 3 Instruct has broader tracked provider coverage for fallback and procurement flexibility.
  • Mistral Medium 3 Instruct uniquely exposes Vision and Multimodal in local model data.
  • Local decision data tags Mistral Medium 3 Instruct for Long context and Vision.

Monthly cost at traffic

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

Codex 1

Unavailable

No complete token price in local provider data

Mistral Medium 3 Instruct

$820

Cheapest tracked route/tier: Mistral AI Studio

Cost delta unavailable until both models have sourced input and output token prices.

Switch friction

Codex 1 -> Mistral Medium 3 Instruct
  • No overlapping tracked provider route is sourced for Codex 1 and Mistral Medium 3 Instruct; plan for SDK, billing, or endpoint changes.
  • Check replacement coverage for Reasoning and Code execution before moving production traffic.
  • Mistral Medium 3 Instruct adds Vision and Multimodal in local capability data.
Mistral Medium 3 Instruct -> Codex 1
  • No overlapping tracked provider route is sourced for Mistral Medium 3 Instruct and Codex 1; plan for SDK, billing, or endpoint changes.
  • Check replacement coverage for Vision and Multimodal before moving production traffic.
  • Codex 1 adds Reasoning and Code execution in local capability data.

Specs

Specification
Released2025-05-162025-10-01
Context window192k128k
Parameters
ArchitectureDecoder OnlyDecoder Only
LicenseProprietaryProprietary
OpennessProprietaryProprietary
Commercial useCommercial use: conditionalCommercial use: conditional
Knowledge cutoff-2025-03

Pricing and availability

Pricing attributeCodex 1Mistral Medium 3 Instruct
Input price-$0.40/1M tokens
Output price-$2/1M tokens
Providers-

Capabilities

CapabilityCodex 1Mistral Medium 3 Instruct
VisionNoYes
MultimodalNoYes
ReasoningYesNo
Function callingNoNo
Tool useNoNo
Structured outputsNoNo
Code executionYesNo
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

No shared benchmark scores are currently available for this pair.

Deep dive

The capability footprint differs most on vision: Mistral Medium 3 Instruct, multimodal input: Mistral Medium 3 Instruct, reasoning mode: Codex 1, and code execution: Codex 1. 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: Codex 1 has no token price sourced yet and Mistral Medium 3 Instruct has $0.40/1M input tokens. Provider availability is 0 tracked routes versus 2. Treat unknown pricing as an integration gap, then verify the route you will actually call before estimating production spend.

Choose Codex 1 when coding workflow support and larger context windows are central to the workload. Choose Mistral Medium 3 Instruct when vision-heavy evaluation 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, Codex 1 or Mistral Medium 3 Instruct?

Codex 1 supports 192k tokens, while Mistral Medium 3 Instruct supports 128k tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.

Is Codex 1 or Mistral Medium 3 Instruct open source?

Codex 1 is listed under Proprietary. Mistral Medium 3 Instruct is listed under Proprietary. 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, Codex 1 or Mistral Medium 3 Instruct?

Mistral Medium 3 Instruct has the clearer documented vision signal in this comparison. If vision is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Which is better for multimodal input, Codex 1 or Mistral Medium 3 Instruct?

Mistral Medium 3 Instruct 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 reasoning mode, Codex 1 or Mistral Medium 3 Instruct?

Codex 1 has the clearer documented reasoning mode signal in this comparison. If reasoning mode is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Where can I run Codex 1 and Mistral Medium 3 Instruct?

Codex 1 is available on the tracked providers still being sourced. Mistral Medium 3 Instruct is available on NVIDIA NIM and Mistral AI Studio. Provider coverage can affect latency, region availability, compliance posture, and fallback options.

Continue comparing

Last reviewed: 2026-06-15. Data sourced from public model cards and provider documentation.