Bolt.new starts at $20/month for 10 million tokens, but the real cost is measured in context windows. Unlike standard chat interfaces, Bolt runs a complete Node.js environment directly in your browser using StackBlitz’s WebContainers. This allows it to install npm packages, run backend servers, and see the results instantly without spinning up a cloud VM.
For a developer building a fresh MVP, the math is compelling. A typical "edit-run-debug" loop might consume 50,000 tokens of context if your project files are included. On the $20 plan (10M tokens), you get roughly 200 significant iterations per month. That’s enough for a focused sprint, but if you’re refactoring a large legacy codebase, you’ll burn through that allowance in a weekend. The token counter ticks up fast because every file the agent reads counts against your quota.
The technical achievement here is the zero-latency feedback loop. Because the code executes client-side, there’s no "waiting for container provision" time. You type a prompt, the agent writes code, and the preview updates instantly. It feels less like asking an AI to write code and more like pair programming with a very fast junior dev who has instant access to npm.
However, the browser-based architecture is also its glass ceiling. WebContainers are strictly Node.js environments. If your stack needs Python (FastAPI/Django), Go, or Docker, Bolt hits a wall. You can’t run a Python backend in the browser effectively yet. Additionally, because it runs in your tab, large applications can crash the browser process due to memory limits.
The real differentiator is the "eject" button: bolt.diy. This is the open-source version that lets you bypass the SaaS limits entirely and use your own API keys (Anthropic, OpenAI, etc.). If you’re cost-conscious and technical, running the open-source version locally gives you the best of both worlds—the agentic workflow without the markup.
Skip Bolt.new if you need non-JS backends or persistence (use Replit Agent). Use it if you are a JavaScript/TypeScript developer who wants to go from idea to deployed prototype in a single afternoon without touching a terminal.
Pricing
The Free Tier offers ~150k-300k tokens daily with a hard 1M monthly cap. In practice, 300k tokens is often just 5-10 complex "fix this error" turns once your project grows beyond a few files. The cliff is steep: once you hit the daily limit, you are locked out until UTC midnight. The $20 Pro plan removes the daily cap and gives 10M tokens, effectively 10x the utility.
Competitively, Replit Agent charges $20/month + usage limits that feel looser because they aren't strictly exposed as tokens in the same way. The hidden cost with Bolt is the context bloat—as your app grows, every prompt costs more, accelerating your burn rate.
Technical Verdict
Bolt's reliance on WebContainers is its superpower and its kryptonite. The Node.js runtime is 100% local, meaning zero server latency for builds, but it restricts you strictly to the JavaScript ecosystem (Next.js, Remix, Vite). There is no API or SDK to integrate Bolt into an external pipeline; it is a standalone browser IDE. The open-source bolt.diy is a high-quality escape hatch, allowing you to run the agent locally with your own LLM keys, which is rare in this category.
Quick Start
import subprocess
# Bolt.new is a browser tool, but you can run the open-source engine locally.
# This requires Node.js/npm to be installed.
print("Cloning and starting bolt.diy (Bring Your Own Keys version)...")
subprocess.run("npx bolt.diy", shell=True)
# Output:
# > Starting Bolt.new local development server at http://localhost:5173Watch Out
- Strictly Node.js only; cannot run Python (FastAPI/Flask) or Go backends inside the browser container.
- Browser memory limits will crash the tab if your application build process requires >4GB RAM.
- Token usage scales with project size; a simple 'fix this' command on a large codebase can cost $0.50+ in equivalent tokens.
- No persistent storage; if you don't deploy or sync to GitHub, closing the tab effectively wipes the VM state.