Chat with Claude Sonnet 4.6 for free
Claude Sonnet 4.6 is the everyday workhorse, quick, capable and cost-effective for the bulk of day-to-day tasks. Start typing, no sign-up needed.
See how Claude Sonnet 4.6 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 Claude Sonnet 4.6 stand out
Claude Sonnet 4.6 specifications
| Provider | Anthropic |
| Model family | Claude 4 series |
| Context window | 1,000,000 tokens |
| Max output | 128,000 tokens |
| Modality | Text · Vision · Code |
| Input price | $3 / 1M tokens |
| Output price | $15 / 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.
Claude Sonnet 4.6 vs other top models
| Model | Context | Best at | Input price | In Chatday |
|---|---|---|---|---|
| Claude Sonnet 4.6 | 1M | Balanced | $3/M | Free |
| GPT-5.5 | 1M | Flagship reasoning | $5/M | Free |
| Gemini 3.1 Pro | 1M | Multimodal | $2/M | Free |
| Grok 4 | 1M | Realtime | $0.2/M | Free |
Claude Sonnet 4.6 questions
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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 Claude Sonnet 4.6 and switch models any time.
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