Chat with GPT-6.1 for free
GPT-6.1 is OpenAI's newest flagship for agentic coding, computer use and professional work, with a 1M-token context and configurable reasoning. Start typing, no sign-up needed.
See how GPT-6.1 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 GPT-6.1 stand out
GPT-6.1 specifications
| Provider | OpenAI |
| Model family | GPT-6 series |
| Context window | 1,050,000 tokens |
| Max output | 128,000 tokens |
| Modality | Text · Vision · Code |
| Input price | $2 / 1M tokens |
| Output price | $10 / 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.
GPT-6.1 vs other top models
| Model | Context | Best at | Input price | In Chatday |
|---|---|---|---|---|
| GPT-6.1 | 1.1M | Agentic coding | $2/M | Free |
| Grok 4.6 | 500K | Agentic reasoning | $2/M | Free |
| Claude Opus 5 | 1M | Frontier agents | $5/M | Free |
| Gemini 3.1 Pro | 1M | Multimodal | $2/M | Free |
GPT-6.1 questions
Other models
Grok 4.6
Grok 4.6 is xAI's flagship for long agentic runs, with self-checking on multi-step tasks and strong coding at half frontier prices.
Claude Opus 5
Claude Opus 5 is Anthropic's strongest Opus model: hybrid reasoning for long-running agents, serious coding and computer use.
Gemini 3.1 Pro
Gemini 3.1 Pro is natively multimodal across text, image, audio and video, with the largest context window available and fast, fresh answers.
Chat with GPT-6.1 and switch models any time.
One subscription, every leading model. Start free in the Chatday web app.