Gemini 3 Flash Preview vs GPT-5.1-Codex-Mini
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 Gemini 3 Flash Preview if you need
- ✓Choose GPT-5.1-Codex-Mini if you need strong coding specialization with native image and text support.
- ✓Choose GPT-5.1-Codex-Mini if you need faster output at 214.62 t/s and lower price of $2 per million tokens.
- ✓Choose GPT-5.1-Codex-Mini if you need a 400k context window optimized for extended technical workflows.
- ✓Choose GPT-5.1-Codex-Mini if you need a stable proprietary model without preview-stage instability.
Choose GPT-5.1-Codex-Mini if you need
- ✓Choose Gemini 3 Flash Preview if you need higher intelligence at 46.4 index for complex multimodal tasks.
- ✓Choose Gemini 3 Flash Preview if you need the largest 1M-token context and support for text, image, audio, video and files.
- ✓Choose Gemini 3 Flash Preview if you need efficient handling of very large contexts across multiple modalities.
- ✓Choose Gemini 3 Flash Preview if you need broad native multimodal coverage beyond image and text.
Verdict
Gemini 3 Flash Preview leads in raw intelligence and context scale while GPT-5.1-Codex-Mini wins on speed and price for coding-focused multimodal work. Gemini's 46.4 intelligence index and 1M-token context outperform GPT-5.1-Codex-Mini's 38.6 index and 400k context, yet GPT-5.1-Codex-Mini delivers faster output at 214.62 t/s versus 188.42 t/s and lower cost at $2/1M versus $3/1M. GPT-5.1-Codex-Mini specializes in coding with image+text support, whereas Gemini adds native audio and video handling.
Gemini 3 Flash Preview vs GPT-5.1-Codex-Mini: side by side
| Spec | Gemini 3 Flash Preview | GPT-5.1-Codex-Mini | Winner |
|---|---|---|---|
| Intelligence | 46.4 | 38.6 | Gemini 3 Flash Preview |
| Output speed | 188 t/s | 215 t/s | GPT-5.1-Codex-Mini |
| Output price | $3.00/1M | $2.00/1M | GPT-5.1-Codex-Mini |
| Context | 1049K | 400K | Gemini 3 Flash Preview |
| Params | — | — | Tie |
| Type | Proprietary | Proprietary | Tie |
| Provider | OpenAI | Tie |
Detailed analysis
Intelligence
Winner: Gemini 3 Flash PreviewGemini 3 Flash Preview scores 46.4 on the intelligence index compared to GPT-5.1-Codex-Mini's 38.6. This gives Gemini an edge on general reasoning depth despite its preview status. GPT-5.1-Codex-Mini's lower score aligns with its noted limitation on complex reasoning as a mini variant.
Speed and Pricing
Winner: GPT-5.1-Codex-MiniGPT-5.1-Codex-Mini outputs at 214.62 tokens per second versus Gemini 3 Flash Preview's 188.42 t/s. It also costs $2 per million tokens compared to Gemini's $3 per million. These advantages make GPT-5.1-Codex-Mini more efficient for high-volume coding workflows.
Context and Modalities
Winner: Gemini 3 Flash PreviewGemini 3 Flash Preview provides a 1,048,576-token context window versus GPT-5.1-Codex-Mini's 400,000 tokens. It natively supports text, image, audio, video and files while GPT-5.1-Codex-Mini is limited to image and text. GPT-5.1-Codex-Mini trades some scale for coding specialization within its smaller window.
Specialization
Winner: GPT-5.1-Codex-MiniGPT-5.1-Codex-Mini is explicitly positioned as a multimodal coding model with strengths in extended technical workflows. Gemini 3 Flash Preview focuses on broad multimodal preview tasks without mentioned coding specialization. This makes GPT-5.1-Codex-Mini the clearer choice for code-centric image+text work.
Gemini 3 Flash Preview
Pros
- +Broad native support for text, image, audio, video and files
- +Efficient handling of very large contexts
- +Fast inference suitable for preview use
Cons
- –Preview status may include occasional instability
- –Reasoning depth can be shallower than full-scale models
- –No native tool-use or external browsing mentioned
GPT-5.1-Codex-Mini
Pros
- +Very large context window
- +Strong coding specialization
- +Native image + text support
- +Suitable for extended technical workflows
Cons
- –Mini variant may have reduced depth on complex reasoning
- –Limited to image and text modalities
- –Trade-off between context size and response speed
Summary: Gemini 3 Flash Preview vs GPT-5.1-Codex-Mini
Select GPT-5.1-Codex-Mini for faster, cheaper coding tasks that fit within a 400k context and image+text needs. Choose Gemini 3 Flash Preview when higher intelligence, a 1M context, and full audio/video support are required. The decision hinges on whether coding speed or broad multimodal scale matters most.
Frequently asked questions
Gemini 3 Flash Preview is stronger on intelligence and context size while GPT-5.1-Codex-Mini leads on speed, price, and coding focus; neither dominates every dimension.