Chat with Claude Haiku 4.5 for free
Claude Haiku 4.5 is the fastest Claude, tuned for snappy, lightweight tasks where responsiveness is everything. Start typing, no sign-up needed.
See how Claude Haiku 4.5 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 Haiku 4.5 stand out
Claude Haiku 4.5 specifications
| Provider | Anthropic |
| Model family | Claude 4 series |
| Context window | 200,000 tokens |
| Max output | 64,000 tokens |
| Modality | Text · Vision · Code |
| Input price | $1 / 1M tokens |
| Output price | $5 / 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 Haiku 4.5 vs other top models
| Model | Context | Best at | Input price | In Chatday |
|---|---|---|---|---|
| Claude Haiku 4.5 | 200K | Fast | $1/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 Haiku 4.5 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 Haiku 4.5 and switch models any time.
One subscription, every leading model. Start free in the Chatday web app.