#1 on LongMemEval-S
c137 — AI chat with persistent long-term memory, document citations, and editing.
The only AI that cites its own memory.
The only AI that cites its own memory.
Import your chat history and c137 builds its memory from it — everything you've already explained, remembered from your first message.
Models
Claude, GPT, Gemini, Grok, DeepSeek, Qwen, Kimi, GLM, MiniMax — all included. Bring your own key on any family and pay less. Anything else, plug in an OpenRouter key.
Documents
Page-level citations. Edit in place. Download in your format.
Scoped Memory
Memory is scoped — to a chat, a project, or you. Chats in a project share it automatically. Nothing else crosses unless you @ it.
Benchmarks
SOTA score, 10x more token efficient, solo dev.
Every feature, every plan. Upgrade when you need more.
Everything you need
then £10/month · cancel anytime
For power users
Everything you need to know about c137.
c137 manages context efficiently, so chats stay fast no matter how long they get and don't forget what matters. Other apps reset or slow to a crawl. c137 keeps going.
Every conversation adds to what c137 knows about you. It remembers your projects, preferences, and context long-term. No manual setup — it just picks up what matters.
Yes. From ChatGPT, Claude, Grok, Gemini or any other chat app — copy the prompt, paste the output, and start chatting here. That's it.
Yes. Every new account gets 5,000 free credits. No card required. When you run out, subscribe to keep going.
All frontier models — GPT, Claude, Grok, Gemini and more. Or bring your own key via the providers directly or OpenRouter for more control.
Your conversations stay in your account, and we never sell them. No model you chat with trains on your data — the majors (OpenAI, Anthropic, Google, xAI) hold it only briefly for abuse monitoring, and every other model runs with data collection disabled. One provider that handles internal memory processing is still finalizing those same terms in writing — we say so plainly rather than round up. You can see and edit everything the AI remembers, and delete or export all of it whenever you want. The full breakdown — every provider, what they keep, where your data lives — is on the Your Data page.