Chat with Gemini 3.1 Pro for free
Gemini 3.1 Pro is natively multimodal across text, image, audio and video, with the largest context window available and fast, fresh answers. Start typing, no sign-up needed.
See how Gemini 3.1 Pro thinks
Pick a task and watch a sample answer stream in. Open the same prompt in Chatday when you’re ready.
The bug is in the arrow body: u.id = id assigns instead of compares, so the callback returns the assigned value and .find never matches the way you expect.
Fix it with a strict comparison:
Use === to compare. A single = is assignment, which is why you saw undefined.
What makes Gemini 3.1 Pro stand out
Gemini 3.1 Pro specifications
| Provider | |
| Model family | Gemini 3 series |
| Context window | 1,000,000 tokens |
| Max output | 64,000 tokens |
| Modality | Text · Vision · Audio · Video · Code |
| Input price | $2 / 1M tokens |
| Output price | $12 / 1M tokens |
| Tool / function calling | Yes |
| Vision | Yes |
| Streaming | Yes |
| Available in Chatday | Free & Pro |
Pricing shown for reference; usage is included in your Chatday plan.
Gemini 3.1 Pro vs other top models
| Model | Context | Best at | Input price | In Chatday |
|---|---|---|---|---|
| Gemini 3.1 Pro | 1M | Multimodal | $2/M | Free |
| Claude Opus 4.8 | 1M | Frontier coding | $5/M | Free |
| GPT-5.5 | 1M | Flagship reasoning | $5/M | Free |
| Grok 4 | 1M | Realtime | $0.2/M | Free |
Gemini 3.1 Pro questions
Other models
Claude Opus 4.8
Claude Opus 4.8 is Anthropic's strongest model for coding, agentic tasks and enterprise work, with a 1M-token context window.
GPT-5.5
GPT-5.5 is OpenAI's flagship model for hard, multi-step reasoning, coding and tool use, the default when problems get genuinely difficult.
Grok 4
Grok 4 pairs realtime knowledge with a direct, witty tone and live web search, strong on current events and fresh information.
Chat with Gemini 3.1 Pro and switch models any time.
One subscription, every leading model. Start free in the Chatday web app.