A chat you can just open and use.
ChatHaiku is free, needs no account, and starts the moment the page loads. Pick a model, type a question, read the reply.
Which model to use
Epos 3 is the current model and the right answer for almost everything. Epos 2.1, the model it replaces, is still here if you prefer it.
Current model
Epos 3
Built for the things people actually use a chat for: everyday questions, writing and fixing code, thinking a plan through, working out logic. It is better than Epos 2.1 across the board, and it was trained specifically to be good at looking things up rather than guessing.
- Knowledge test (MMLU)
- 60.05% one-shot
- Looks things up
- Web and documents
Not sure? Choosing a model compares them, and you can switch mid-conversation without losing it. Older and retired models are archived at every Rootcomputer model.
What you can do in the chat
Everything below is on by default or one tap away. Nothing needs setting up.
- Listen instead of reading
- Any reply can be read aloud in one of eleven voices, and you can dictate your message instead of typing it. Voice and audio
- Change how it writes
- Casual for everyday chat, Logical when you want the same answer twice, Creative for brainstorming. Extended replies when you need the model to work through something properly. Response controls
- Branch instead of starting over
- Go back to any earlier message and take the conversation a different way, keeping the part that was working. Conversations
- Edit, retry, compare
- Reword your question and send it again, ask for another attempt, or put two replies side by side and pick the better one. Working with messages
- Watch it think
- On the Epos models you can open the reasoning behind a reply and see the steps it took before answering.
- Make it yours
- Light or dark, four animated new-chat backgrounds, and a reply typeface that includes a dyslexia-friendly option. Appearance
Your conversations stay on your device
ChatHaiku has no accounts and keeps no chat history on a server. Every conversation is stored in your own browser, which means it is private to this device by default — and it also means clearing your browser data deletes it for good.
Your message is sent to Rootcomputer's hardware to generate a reply, and is not kept afterwards unless you rate it with the thumbs buttons. Your data and privacy has the full picture.
Small models, honestly
These models are small on purpose. Epos 2.1 is 1.5 billion parameters, against the hundreds of billions in a frontier system. That is why they answer quickly and run on modest hardware, and it is also why they get things wrong more often — even with Epos 3 checking its sources. Verify anything that matters.
They are trained and run by Rootcomputer Development on its own machines, and measured against Featherweight, a benchmark written for models of this size. The full evaluation has the numbers.
Because the hardware is ours, models occasionally go offline for training or maintenance. The status page shows live health for each one, thirty days of history, and any current incident.