Vibe coding, free. Say what you want in plain words. The agent builds it, runs it and checks its own work.
What vibe coding is
You describe the result, not the code: “a page that lists my orders with a search box”. The agent decides how, writes it and shows you what it did. You steer with follow-ups.
Plan first when it matters
For a bigger change, ask for a plan. The agent reads your code, writes the plan as a document and asks what it needs to know before it builds.
It checks its own work
The agent runs the app and the tests itself and keeps going until they pass, so what you vibe-coded actually works when it says it is done.
Free to start
Free costs nothing and needs no card: the agent in your terminal, your editor and the Mac app, the free models, and your own API keys and local models (Ollama, LM Studio) with no limits from us. Paid plans start at $8 a month (Plus) and go up to $200 (Ultra). They include GLM, Kimi, MiniMax, DeepSeek, Qwen, Grok and Auto with a session limit and a weekly limit you can always see; from Pro ($30) Claude, GPT and Gemini are paid from credits.
Questions
What is vibe coding?+
Building software by describing what you want in plain language and letting an AI agent write, run and fix the code, while you review the result and steer with follow-ups.
Is there a free vibe coding tool?+
Yes, MegaBrain. Free costs nothing and needs no card: the agent in your terminal, your editor and the Mac app, the free models, and your own API keys and local models (Ollama, LM Studio) with no limits from us.
Do I need to know how to code?+
It helps to be able to read what the agent changed, but you do not have to write it. Ask the agent to explain any change in plain words before you keep it.
Which model is best for vibe coding?+
Let Auto pick: it chooses a model per task. On the paid plans GLM, Kimi and MiniMax go far on the plan’s limits; Claude, GPT and Gemini are there from Pro when a task needs them.
How do I start?+
Install the CLI with npm install -g @getmegabrain/cli, run megabrain in your project and sign in once. Or download MegaBrain for Mac (macOS 13 or later on Apple silicon (M1 or newer)).
More free AI coding tools
Free AI Code Generator
Describe what you want. The agent writes it across your files, runs it and fixes what fails.
Free AI Coding Assistant for Your IDE
An agent, not autocomplete: it plans, edits across files and runs your tests.
AI Coding Agent for the Terminal
It reads your repo, plans, edits across files, runs your tests and commits. Free to start.
Cursor Alternative with a Free Plan
The same prices, open models on the plan from $8, and your own keys free.