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E2B

Let your AI agent execute real code in a secure cloud sandbox — spins up in 150ms, runs Python and JavaScript safely, and tears down cleanly when done.

Developer Tools
4.5freemium

E2B — the verdict: Developers who need agents to run untrusted code safely without touching their own infrastructure E2B's job is to let an AI agent execute real code without touching your infrastructure or running untrusted scripts in your environment. Pricing: Free 100 sandbox-hrs/mo / $150/mo Pro. Last reviewed: August 2026.

Best For

Developers who need agents to run untrusted code safely without touching their own infrastructure

Standout Feature

Sandboxed cloud VMs spin up in under 150ms, fast enough for interactive agentic reasoning loops

Verdict

A clean solution to unsafe code execution, sandboxes are ephemeral by default so persistent state needs explicit setup.

Alternatives

Overview

E2B provides sandboxed code execution environments for AI agents — secure, isolated cloud VMs that spin up in under 150ms and let agents run, test, and iterate on code without touching your infrastructure. Each sandbox is fully ephemeral and isolated so agents can execute untrusted code safely. Integrates with Claude, GPT-4o, and any agent framework that generates code as part of its reasoning loop.

Our Take

E2B's job is to let an AI agent execute real code without touching your infrastructure or running untrusted scripts in your environment. Sandboxed cloud VMs spin up in under 150ms, which is fast enough for interactive agentic reasoning loops where the agent writes code, runs it, reads the output, and iterates. Each sandbox is ephemeral and isolated by default. That default is also the main constraint: if your agent needs state to persist across sandbox sessions, you have to set that up explicitly. Sandbox compute is metered, so long-running agents can get expensive at the 100-hour free tier ceiling before the $150 per month Pro plan. The right fit is a developer building an agent that needs safe code execution without the infrastructure overhead.

Key Features

  • Sandboxed cloud VMs with 150ms cold start times
  • Python, JavaScript, Bash, and custom Docker environments
  • File system access, network calls, and package installation inside sandbox
  • SDK integrations for Claude, GPT-4o, Gemini, and LangChain
  • Persistent sandbox state across multi-step agent runs
  • Custom sandbox templates via Dockerfile
Pros
  • Solves unsafe code execution cleanly — no infrastructure risk
  • Fast enough (150ms) for interactive agentic reasoning loops
  • Free tier is generous for development and prototyping
Cons
  • Ephemeral by default — persistent state requires explicit config
  • Sandbox compute is metered — long-running agents can get expensive
  • Network access inside sandbox may need allowlisting for enterprise use

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