GPT-5.1-Codex-Max vs GPT-5.5
A side-by-side comparison of two multimodal models — real specs, pricing, strengths and weaknesses, and a clear verdict on which to choose. Kept current by our agents.
Quick verdict: which should you choose?
Choose GPT-5.1-Codex-Max if you need
- ✓Choose GPT-5.1-Codex-Max if you need lower output cost at $10 per million tokens.
- ✓Choose GPT-5.1-Codex-Max if you need a strong coding focus with text and image inputs.
- ✓Choose GPT-5.1-Codex-Max if you need 400k-token context for complex technical workflows.
- ✓Choose GPT-5.1-Codex-Max if you need to avoid the higher latency risks of 1M+ contexts.
Choose GPT-5.5 if you need
- ✓Choose GPT-5.5 if you need the largest context window at 1.05M tokens.
- ✓Choose GPT-5.5 if you need native support for massive file, image, and text inputs.
- ✓Choose GPT-5.5 if you need measured output speed of 58.54 tokens per second.
- ✓Choose GPT-5.5 if you need document-heavy multimodal workflows.
Verdict
GPT-5.5 leads in raw context scale (1.05M vs 400k tokens) and documented output speed while GPT-5.1-Codex-Max undercuts it by two-thirds on price and targets coding workflows. GPT-5.5 adds native file handling for document tasks; both remain limited to text and image inputs with no audio or video support. The choice hinges on whether budget and coding focus outweigh the need for maximum context and file flexibility.
GPT-5.1-Codex-Max vs GPT-5.5: side by side
| Spec | GPT-5.1-Codex-Max | GPT-5.5 | Winner |
|---|---|---|---|
| Intelligence | — | 43.5 | Tie |
| Output speed | — | 59 t/s | Tie |
| Output price | $10.00/1M | $30.00/1M | GPT-5.1-Codex-Max |
| Context | 400K | 1050K | GPT-5.5 |
| Params | — | — | Tie |
| Provider | OpenAI | OpenAI | Tie |
Detailed analysis
Context Size
Winner: GPT-5.5GPT-5.5 provides a 1,050,000-token context while GPT-5.1-Codex-Max offers 400,000 tokens. The larger window in GPT-5.5 directly supports its stated strength for massive file and document inputs. Both models incur higher resource demands as context grows.
Pricing
Winner: GPT-5.1-Codex-MaxGPT-5.1-Codex-Max lists output pricing at $10 per million tokens versus $30 per million for GPT-5.5. No input pricing or other cost factors are provided for either model. The threefold price difference favors GPT-5.1-Codex-Max on cost-sensitive workloads.
Multimodal Capabilities
Winner: TieBoth models accept text and image inputs and lack native audio or video support. GPT-5.5 explicitly adds native file handling while GPT-5.1-Codex-Max emphasizes text-plus-image combinations. Neither model extends beyond these modalities according to the given facts.
Task Focus
Winner: GPT-5.1-Codex-MaxGPT-5.1-Codex-Max highlights a strong coding focus and suitability for complex technical workflows. GPT-5.5 instead targets document-heavy tasks and flexible multimodal file workflows. The documented strengths therefore align each model to different primary use cases.
GPT-5.1-Codex-Max
Pros
- +Handles very large contexts
- +Strong coding focus
- +Combines text and image inputs
Cons
- –Limited to text and image modalities
- –High resource demands for large contexts
- –No support for other media types
GPT-5.5
Pros
- +Extremely large context window
- +Native support for files and images
- +Flexible multimodal workflows
Cons
- –No native audio or video support
- –Large context may increase latency
- –Performance depends on input quality across modalities
Summary: GPT-5.1-Codex-Max vs GPT-5.5
Select GPT-5.1-Codex-Max when coding tasks and lower token cost matter most within a 400k context. Choose GPT-5.5 when maximum context, file support, and measured speed are required despite the higher price. Both models share the same provider, proprietary status, and text-plus-image modality limits.
Frequently asked questions
GPT-5.1-Codex-Max is cheaper at $10 per million output tokens compared with $30 per million for GPT-5.5.