GPT-5 vs GPT-5.5 Pro
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 if you need
- ✓Choose GPT-5 if you need a documented output speed of 165.35 t/s and intelligence_index of 15.3.
- ✓Choose GPT-5 if you need the lower price of $10 per million tokens.
- ✓Choose GPT-5 if you need a 400k-token context with seamless text-image-file integration.
- ✓Choose GPT-5 if you need a model whose performance metrics are already specified.
Choose GPT-5.5 Pro if you need
- ✓Choose GPT-5.5 Pro if you need the largest context window at 1.05 million tokens.
- ✓Choose GPT-5.5 Pro if you need strong reasoning over extended multimodal inputs.
- ✓Choose GPT-5.5 Pro if you need native support for files, images, and text at maximum scale.
- ✓Choose GPT-5.5 Pro if you need the 1M+ token context despite higher cost.
Verdict
GPT-5 leads on verified metrics with a known intelligence_index of 15.3, output speed of 165.35 t/s, and far lower price at $10 per million tokens, while GPT-5.5 Pro leads on raw context size at 1.05 million tokens versus 400k. Both share OpenAI proprietary status and native multimodal support for text, images, and files, but GPT-5.5 Pro's higher $180 price and missing performance data leave its advantages unquantified. GPT-5 is the more practical choice where speed and cost matter; GPT-5.5 Pro wins only when maximum context length is required.
GPT-5 vs GPT-5.5 Pro: side by side
| Spec | GPT-5 | GPT-5.5 Pro | Winner |
|---|---|---|---|
| Intelligence | 15.3 | — | Tie |
| Output speed | 165 t/s | — | Tie |
| Output price | $10.00/1M | $180.00/1M | GPT-5 |
| Context | 400K | 1050K | GPT-5.5 Pro |
| Params | — | — | Tie |
| Provider | OpenAI | OpenAI | Tie |
Detailed analysis
Context Window
Winner: GPT-5.5 ProGPT-5.5 Pro provides 1,050,000 tokens compared with GPT-5's 400,000 tokens. Both models list very large context as a strength, yet only GPT-5.5 Pro exceeds one million tokens. This gives GPT-5.5 Pro the edge for tasks requiring the longest inputs.
Pricing
Winner: GPT-5GPT-5 is priced at $10 per million tokens while GPT-5.5 Pro costs $180 per million tokens. The 18x price difference is directly stated in the model facts. GPT-5 therefore wins on cost for any usage volume.
Speed & Intelligence
Winner: GPT-5GPT-5 reports an output speed of 165.35 tokens per second and intelligence_index of 15.3. GPT-5.5 Pro lists neither metric. The available data therefore favors GPT-5 on measurable performance.
Multimodal Support
Winner: TieBoth models state native multimodal input for text, images, and files with seamless integration. GPT-5.5 Pro additionally notes strong reasoning over extended inputs but excludes audio and video. The core multimodal capabilities are equivalent based on the given facts.
GPT-5
Pros
- +Very large context window
- +Native multimodal input support
- +Seamless text-image-file integration
Cons
- –Hypothetical model with unverified performance
- –High resource demands for maximum context
- –Potential latency on large multimodal tasks
GPT-5.5 Pro
Pros
- +Very large context window
- +Native support for files, images, and text
- +Seamless multimodal integration
Cons
- –High resource use with maximum context
- –No audio or video modalities
- –Potential latency on very long inputs
Summary: GPT-5 vs GPT-5.5 Pro
Select GPT-5 when speed, cost, and known metrics are priorities. Select GPT-5.5 Pro only when the 1.05-million-token context is essential. All other dimensions either favor GPT-5 or result in a tie.
Frequently asked questions
GPT-5 is better on every quantified dimension except context length; GPT-5.5 Pro is better only on raw context size.