LLM Reference

GPT-5.3-Codex vs Hunyuan Hy3 Preview

GPT-5.3-Codex (2026) and Hunyuan Hy3 Preview (2026) compare a coding-specialized model against a standalone API model. GPT-5.3-Codex ships a 400k-token context window, while Hunyuan Hy3 Preview ships a 262k-token context window. On SWE-bench Verified, GPT-5.3-Codex leads by 10.6 pts. On pricing, Hunyuan Hy3 Preview costs $0.07/1M input tokens versus $1.75/1M for the alternative. 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 Hunyuan Hy3 Preview 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-CodexHunyuan Hy3 Preview
Product typeCoding-specialized modelStandalone API model
Best forcustom coding agents, code generation, and tool loopsreasoning-heavy apps, tool-calling agents, and provider-routed production
Decision fitCoding, RAG, and AgentsCoding, RAG, and Agents
Context window400k262k
Cheapest output$14/1M tokens$0.26/1M tokens
Provider routes3 tracked2 tracked
Shared benchmarksSWE-bench Verified leader2 rows

Decision tradeoffs

Choose GPT-5.3-Codex when...
  • GPT-5.3-Codex holds a shared-benchmark lead on SWE-bench Verified, ahead by 10.6 points.
  • 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, Structured outputs, and Code execution in local model data.
  • Local decision data tags GPT-5.3-Codex for Coding, RAG, and Agents.
Choose Hunyuan Hy3 Preview when...
  • Hunyuan Hy3 Preview has the lower cheapest tracked output price at $0.26/1M tokens.
  • Local decision data tags Hunyuan Hy3 Preview 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 Hunyuan Hy3 Preview

GPT-5.3-Codex

$4,900

Cheapest tracked route/tier: OpenRouter

Hunyuan Hy3 Preview

$118

Cheapest tracked route/tier: OpenRouter

Estimated monthly gap: $4,782. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.

Switch friction

GPT-5.3-Codex -> Hunyuan Hy3 Preview
  • Provider overlap exists on OpenRouter; start route-level A/B tests there.
  • Hunyuan Hy3 Preview is $13.74/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
  • Check replacement coverage for Vision, Structured outputs, and Code execution before moving production traffic.
Hunyuan Hy3 Preview -> GPT-5.3-Codex
  • Provider overlap exists on OpenRouter; start route-level A/B tests there.
  • GPT-5.3-Codex is $13.74/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
  • GPT-5.3-Codex adds Vision, Structured outputs, and Code execution in local capability data.

Specs

Specification
Released2026-02-052026-04-22
Context window400k262k
Parameters295B
Architecturedecoder onlydense moe hybrid
LicenseProprietaryTencent Hunyuan Community License
OpennessProprietaryOpen weights
Commercial useCommercial use with conditionsCommercial use with conditions
Knowledge cutoff2025-08-

Pricing and availability

Pricing attributeGPT-5.3-CodexHunyuan Hy3 Preview
Input price$1.75/1M tokens$0.07/1M tokens
Output price$14/1M tokens$0.26/1M tokens
Providers

Capabilities

CapabilityGPT-5.3-CodexHunyuan Hy3 Preview
VisionYesNo
MultimodalNoNo
ReasoningYesYes
Function callingYesYes
Tool useYesYes
Structured outputsYesNo
Code executionYesNo
IDE integrationNoNo
Computer useYesNo
Parallel agentsNoNo

Benchmarks

BenchmarkGPT-5.3-CodexHunyuan Hy3 Preview
SWE-bench Verified85.074.4
Terminal-Bench 2.077.354.4

Deep dive

On shared benchmark coverage, SWE-bench Verified has GPT-5.3-Codex at 85 and Hunyuan Hy3 Preview at 74.4, with GPT-5.3-Codex ahead by 10.6 points; Terminal-Bench 2.0 has GPT-5.3-Codex at 77.3 and Hunyuan Hy3 Preview at 54.4, with GPT-5.3-Codex ahead by 22.9 points. The largest visible gap is 22.9 points on Terminal-Bench 2.0, 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 vision: GPT-5.3-Codex, structured outputs: GPT-5.3-Codex, and code execution: GPT-5.3-Codex. Both models share reasoning mode, 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.

For cost, GPT-5.3-Codex lists $1.75/1M input and $14/1M output tokens on the cheapest tracked provider, while Hunyuan Hy3 Preview lists $0.07/1M input and $0.26/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts Hunyuan Hy3 Preview lower by about $5.30 per million blended tokens. Availability is 3 providers versus 2, so concentration risk also matters.

Choose GPT-5.3-Codex when coding workflow support, larger context windows, and broader provider choice are central to the workload. Choose Hunyuan Hy3 Preview when provider fit and lower input-token cost 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, GPT-5.3-Codex or Hunyuan Hy3 Preview?

GPT-5.3-Codex supports 400k tokens, while Hunyuan Hy3 Preview supports 262k tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.

Which is cheaper, GPT-5.3-Codex or Hunyuan Hy3 Preview?

Hunyuan Hy3 Preview is cheaper on tracked token pricing. GPT-5.3-Codex costs $1.75/1M input and $14/1M output tokens. Hunyuan Hy3 Preview costs $0.07/1M input and $0.26/1M output tokens. Provider discounts or batch pricing can still change the final bill.

Is GPT-5.3-Codex or Hunyuan Hy3 Preview open source?

GPT-5.3-Codex is listed under Proprietary. Hunyuan Hy3 Preview is listed under Tencent Hunyuan Community 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, GPT-5.3-Codex or Hunyuan Hy3 Preview?

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 Hunyuan Hy3 Preview?

Both GPT-5.3-Codex and Hunyuan Hy3 Preview expose reasoning mode. 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 Hunyuan Hy3 Preview?

GPT-5.3-Codex is available on OpenRouter, OpenAI API, and Vercel AI Gateway. Hunyuan Hy3 Preview is available on OpenRouter and Tencent Cloud TI Platform. 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.