LLM Reference

Codex Mini Latest vs GPT-5.3-Codex

Codex Mini Latest (2025) and GPT-5.3-Codex (2026) are agentic coding models from OpenAI. Codex Mini Latest ships a 200k-token context window, while GPT-5.3-Codex ships a 400k-token context window. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads. It focuses on practical selection signals rather than broad model-family marketing.

GPT-5.3-Codex is safer overall; choose Codex Mini Latest when coding workflow support matters.

Decision scorecard

Local evidence first
SignalCodex Mini LatestGPT-5.3-Codex
Best forcustom coding agents and code generationcustom coding agents, code generation, and tool loops
Decision fitCoding and Long contextCoding, RAG, and Agents
Context window200k400k
Cheapest output-$14/1M tokens
Provider routes0 tracked3 tracked
Shared benchmarks0 rows0 rows

Decision tradeoffs

Choose Codex Mini Latest when...
  • Local decision data tags Codex Mini Latest for Coding and Long context.
Choose GPT-5.3-Codex when...
  • GPT-5.3-Codex has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • GPT-5.3-Codex has broader tracked provider coverage for fallback and procurement flexibility.
  • GPT-5.3-Codex uniquely exposes Vision, Reasoning, and Function calling in local model data.
  • Local decision data tags GPT-5.3-Codex 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.

Codex Mini Latest

Unavailable

No complete token price in local provider data

GPT-5.3-Codex

$4,900

Cheapest tracked route/tier: OpenRouter

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

Switch friction

Codex Mini Latest -> GPT-5.3-Codex
  • No overlapping tracked provider route is sourced for Codex Mini Latest and GPT-5.3-Codex; plan for SDK, billing, or endpoint changes.
  • GPT-5.3-Codex adds Vision, Reasoning, and Function calling in local capability data.
GPT-5.3-Codex -> Codex Mini Latest
  • No overlapping tracked provider route is sourced for GPT-5.3-Codex and Codex Mini Latest; plan for SDK, billing, or endpoint changes.
  • Check replacement coverage for Vision, Reasoning, and Function calling before moving production traffic.

Specs

Specification
Released2025-05-162026-02-05
Context window200k400k
Parameters
Architecturedecoder onlydecoder only
LicenseProprietaryProprietary
OpennessProprietaryProprietary
Commercial useCommercial use with conditionsCommercial use with conditions
Knowledge cutoff2024-062025-08

Pricing and availability

Pricing attributeCodex Mini LatestGPT-5.3-Codex
Input price-$1.75/1M tokens
Output price-$14/1M tokens
Providers-

Capabilities

CapabilityCodex Mini LatestGPT-5.3-Codex
VisionNoYes
MultimodalNoNo
ReasoningNoYes
Function callingNoYes
Tool useNoYes
Structured outputsNoYes
Code executionNoYes
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

No shared benchmark rows are currently sourced for this pair.

Deep dive

The capability footprint differs most on vision: GPT-5.3-Codex, reasoning mode: GPT-5.3-Codex, function calling: GPT-5.3-Codex, tool use: GPT-5.3-Codex, structured outputs: GPT-5.3-Codex, and code execution: GPT-5.3-Codex. 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 Mini Latest has no token price sourced yet and GPT-5.3-Codex has $1.75/1M input tokens. Provider availability is 0 tracked routes versus 3. Treat unknown pricing as an integration gap, then verify the route you will actually call before estimating production spend.

Choose Codex Mini Latest when coding workflow support are central to the workload. Choose GPT-5.3-Codex when coding workflow support, larger context windows, 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 Mini Latest or GPT-5.3-Codex?

GPT-5.3-Codex supports 400k tokens, while Codex Mini Latest supports 200k tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.

Is Codex Mini Latest or GPT-5.3-Codex open source?

Codex Mini Latest is listed under Proprietary. GPT-5.3-Codex 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 Mini Latest or GPT-5.3-Codex?

GPT-5.3-Codex 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. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Which is better for reasoning mode, Codex Mini Latest or GPT-5.3-Codex?

GPT-5.3-Codex 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.

Which is better for function calling, Codex Mini Latest or GPT-5.3-Codex?

GPT-5.3-Codex 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 Codex Mini Latest and GPT-5.3-Codex?

Codex Mini Latest is available on the tracked providers still being sourced. GPT-5.3-Codex is available on OpenRouter, OpenAI API, and Vercel AI Gateway. Provider coverage can affect latency, region availability, compliance posture, and fallback options.

Continue comparing

Last reviewed: 2026-05-22. Data sourced from public model cards and provider documentation.