Gemini 2.5 Flash vs GPT-5 Nano
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 2.5 Flash if you need
- ✓higher intelligence (26.8 index) for document reasoning tasks
- ✓much lower cost at $0.4 per 1M output tokens
- ✓efficient handling of large 400k contexts with file inputs
- ✓lightweight design prioritizing faster practical responses
Choose GPT-5 Nano if you need
- ✓maximum output speed of 208.19 tokens per second
- ✓native support for text, image, audio, and video inputs
- ✓very large 1M+ token context window
- ✓strong speed-capability balance across vision and audio tasks
Verdict
GPT-5 Nano leads with a higher intelligence index (26.8 vs 20.6) and far lower price ($0.4 vs $2.5 per 1M tokens) while supporting text, image, and file inputs in a 400k context. Gemini 2.5 Flash counters with superior output speed (208.19 t/s vs 170.06) and a much larger 1M+ context window plus native audio and video support. The choice hinges on whether intelligence and cost or speed and multimodal breadth matter most.
Gemini 2.5 Flash vs GPT-5 Nano: side by side
| Spec | Gemini 2.5 Flash | GPT-5 Nano | Winner |
|---|---|---|---|
| Intelligence | 20.6 | 26.8 | GPT-5 Nano |
| Output speed | 208 t/s | 170 t/s | Gemini 2.5 Flash |
| Output price | $2.50/1M | $0.40/1M | GPT-5 Nano |
| Context | 1049K | 400K | Gemini 2.5 Flash |
| Params | — | — | Tie |
| Type | Proprietary | Proprietary | Tie |
| Provider | OpenAI | Tie |
Detailed analysis
Intelligence
Winner: GPT-5 NanoGPT-5 Nano scores 26.8 on the intelligence index compared to Gemini 2.5 Flash's 20.6. This edge favors it for tasks needing deeper reasoning within its supported modalities. Both models note limitations on highly complex or nuanced work relative to larger variants.
Speed
Winner: Gemini 2.5 FlashGemini 2.5 Flash delivers 208.19 tokens per second versus GPT-5 Nano's 170.06. Its speed optimizations suit high-volume multimodal workloads. GPT-5 Nano's lighter design still provides practical responsiveness but trails in raw throughput.
Pricing
Winner: GPT-5 NanoGPT-5 Nano costs $0.4 per million output tokens while Gemini 2.5 Flash costs $2.5. The sixfold price difference makes Nano markedly more economical for extended use. Both are proprietary models from major providers.
Context & Modalities
Winner: Gemini 2.5 FlashGemini 2.5 Flash offers a 1,048,576-token context versus GPT-5 Nano's 400,000 and adds native audio and video alongside text and image. GPT-5 Nano includes file inputs and handles large contexts efficiently but lacks audio/video breadth.
Gemini 2.5 Flash
Pros
- +Broad native support for multiple input modalities
- +Efficient handling of very large contexts
- +Strong balance of speed and capability
- +Versatile across text, vision and audio tasks
Cons
- –Lower peak performance than larger Gemini variants on complex tasks
- –Speed optimizations may reduce depth on nuanced reasoning
- –Practical limits on full 1M-token context utilization
GPT-5 Nano
Pros
- +Handles very large contexts efficiently
- +Supports text, image, and file inputs
- +Lightweight design for faster responses
- +Practical for extended document tasks
Cons
- –Lower capability depth than full-scale models
- –May struggle with highly complex reasoning
- –Trade-off in advanced task performance
Summary: Gemini 2.5 Flash vs GPT-5 Nano
Select GPT-5 Nano when intelligence depth and low cost are priorities for text-image-file workflows. Choose Gemini 2.5 Flash when maximum speed, the largest context, and audio-video support are required. The models trade off capability and price against throughput and modality range.
Frequently asked questions
GPT-5 Nano scores higher on intelligence (26.8 vs 20.6) and costs far less, while Gemini 2.5 Flash is faster and supports more input types with a larger context.