LLM Reference

GPT-5.3-Codex vs Qwen3-105B

GPT-5.3-Codex (2026) and Qwen3-105B (2025) compare a coding-specialized model against a standalone API model. GPT-5.3-Codex ships a 400k-token context window, while Qwen3-105B 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: GPT-5.3-Codex is coding-specialized model, while Qwen3-105B is standalone API model. Choose based on workflow fit before reading any benchmark or price row as decisive.

Decision scorecard

Local evidence first
SignalGPT-5.3-CodexQwen3-105B
Product typeCoding-specialized modelStandalone API model
Best forcustom coding agents, code generation, and tool loopstool-calling agents
Decision fitCoding, RAG, and AgentsRAG, Agents, and Long context
Context window400k128k
Cheapest output$14/1M tokens-
Provider routes3 tracked0 tracked
Shared benchmarks0 rows0 rows

Decision tradeoffs

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 Structured outputs in local model data.
  • Local decision data tags GPT-5.3-Codex for Coding, RAG, and Agents.
Choose Qwen3-105B when...
  • Local decision data tags Qwen3-105B for RAG, Agents, and Long context.

Monthly cost at traffic

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

GPT-5.3-Codex

$4,900

Cheapest tracked route/tier: OpenRouter

Qwen3-105B

Unavailable

No complete token price in local provider data

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

Switch friction

GPT-5.3-Codex -> Qwen3-105B
  • No overlapping tracked provider route is sourced for GPT-5.3-Codex and Qwen3-105B; plan for SDK, billing, or endpoint changes.
  • Check replacement coverage for Vision, Reasoning, and Structured outputs before moving production traffic.
Qwen3-105B -> GPT-5.3-Codex
  • No overlapping tracked provider route is sourced for Qwen3-105B and GPT-5.3-Codex; plan for SDK, billing, or endpoint changes.
  • GPT-5.3-Codex adds Vision, Reasoning, and Structured outputs in local capability data.

Specs

Specification
Released2026-02-052025-12-15
Context window400k128k
Parameters105B
Architecturedecoder only-
LicenseProprietaryApache 2.0(OSI)
OpennessProprietaryOpen source
Commercial useCommercial use with conditionsCommercial use allowed
Knowledge cutoff2025-082025-02

Pricing and availability

Pricing attributeGPT-5.3-CodexQwen3-105B
Input price$1.75/1M tokens-
Output price$14/1M tokens-
Providers-

Capabilities

CapabilityGPT-5.3-CodexQwen3-105B
VisionYesNo
MultimodalNoNo
ReasoningYesNo
Function callingYesYes
Tool useYesYes
Structured outputsYesNo
Code executionYesNo
IDE integrationNoNo
Computer useYesNo
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, structured outputs: GPT-5.3-Codex, and code execution: GPT-5.3-Codex. Both models share function calling and tool use, 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: GPT-5.3-Codex has $1.75/1M input tokens and Qwen3-105B has no token price sourced yet. Provider availability is 3 tracked routes versus 0. Treat unknown pricing as an integration gap, then verify the route you will actually call before estimating production spend.

Choose GPT-5.3-Codex when coding workflow support, larger context windows, and broader provider choice are central to the workload. Choose Qwen3-105B when provider fit 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. For teams standardizing a stack, that distinction is often the difference between a benchmark win and a reliable deployment.

FAQ

Which has a larger context window, GPT-5.3-Codex or Qwen3-105B?

GPT-5.3-Codex supports 400k tokens, while Qwen3-105B supports 128k tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Is GPT-5.3-Codex or Qwen3-105B open source?

GPT-5.3-Codex is listed under Proprietary. Qwen3-105B 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 vision, GPT-5.3-Codex or Qwen3-105B?

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, GPT-5.3-Codex or Qwen3-105B?

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, GPT-5.3-Codex or Qwen3-105B?

Both GPT-5.3-Codex and Qwen3-105B expose function calling. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Where can I run GPT-5.3-Codex and Qwen3-105B?

GPT-5.3-Codex is available on OpenRouter, OpenAI API, and Vercel AI Gateway. Qwen3-105B is available on the tracked providers still being sourced. Provider coverage can affect latency, region availability, compliance posture, and fallback options.

Continue comparing

Last reviewed: 2026-06-10. Data sourced from public model cards and provider documentation.