Sandbox SDK (Beta)

Build secure, isolated code execution environments

Available on Workers Paid plan

The Sandbox SDK enables you to run untrusted code securely in isolated environments. Built on Containers, Sandbox SDK provides a simple API for executing commands, managing files, running background processes, and exposing services — all from your Workers applications.

Sandboxes are ideal for building AI agents that need to execute code, interactive development environments, data analysis platforms, CI/CD systems, and any application that needs secure code execution at the edge. Each sandbox runs in its own isolated container with a full Linux environment, providing strong security boundaries while maintaining performance.

With Sandbox, you can execute Python scripts, run Node.js applications, analyze data, compile code, and perform complex computations — all with a simple TypeScript API and no infrastructure to manage.

Execute Commands

TypeScript

import { getSandbox } from '@cloudflare/sandbox';

export default {
  async fetch(request: Request, env: Env): Promise<Response> {
    const sandbox = getSandbox(env.Sandbox, 'user-123');

    // Execute a command and get the result
    const result = await sandbox.exec('python --version');

    return Response.json({
      output: result.stdout,
      exitCode: result.exitCode,
      success: result.success
    });
  }
};

Code Interpreter

TypeScript

import { getSandbox } from '@cloudflare/sandbox';

export default {
  async fetch(request: Request, env: Env): Promise<Response> {
    const sandbox = getSandbox(env.Sandbox, 'user-123');

    // Create a Python execution context
    const ctx = await sandbox.createCodeContext({ language: 'python' });

    // Execute Python code with automatic result capture
    const result = await sandbox.runCode(`

import pandas as pd
data = {'product': ['A', 'B', 'C'], 'sales': [100, 200, 150]}
df = pd.DataFrame(data)
df['sales'].sum()  # Last expression is automatically returned
    `, { context: ctx });

    return Response.json({
      result: result.results?.[0]?.text,
      logs: result.logs
    });
  }
};

File Operations

TypeScript

import { getSandbox } from '@cloudflare/sandbox';

export default {
  async fetch(request: Request, env: Env): Promise<Response> {
    const sandbox = getSandbox(env.Sandbox, 'user-123');

    // Create a project structure
    await sandbox.mkdir('/workspace/project/src', { recursive: true });

    // Write files
    await sandbox.writeFile(
      '/workspace/project/package.json',
      JSON.stringify({ name: 'my-app', version: '1.0.0' })
    );

    // Read a file back
    const content = await sandbox.readFile('/workspace/project/package.json');

    return Response.json({ content });
  }
};

Get started

API Reference

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Features

Execute commands securely

Run shell commands, Python scripts, Node.js applications, and more with streaming output support and automatic timeout handling.

Learn about command execution

Manage files and processes

Read, write, and manipulate files in the sandbox filesystem. Run background processes, monitor output, and manage long-running operations.

Learn about file operations

Expose services with preview URLs

Expose HTTP services running in your sandbox with automatically generated preview URLs, perfect for interactive development environments and application hosting.

Learn about preview URLs

Execute code directly

Execute Python and JavaScript code with rich outputs including charts, tables, and images. Maintain persistent state between executions for AI-generated code and interactive workflows.

Learn about code execution

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Use Cases

Build powerful applications with Sandbox:

AI Code Execution

Execute code generated by Large Language Models safely and reliably. Perfect for AI agents, code assistants, and autonomous systems that need to run untrusted code.

Data Analysis & Notebooks

Create interactive data analysis environments with pandas, NumPy, and Matplotlib. Generate charts, tables, and visualizations with automatic rich output formatting.

Interactive Development Environments

Build cloud IDEs, coding playgrounds, and collaborative development tools with full Linux environments and preview URLs.

CI/CD & Build Systems

Run tests, compile code, and execute build pipelines in isolated environments with parallel execution and streaming logs.

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Related products

Containers

Serverless container runtime that powers Sandbox, enabling you to run any containerized workload on the edge.

Workers AI

Run machine learning models and LLMs on the network. Combine with Sandbox for secure AI code execution workflows.

Durable Objects

Stateful coordination layer that enables Sandbox to maintain persistent environments with strong consistency.

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More resources

Tutorials

Explore complete examples including AI code execution, data analysis, and interactive environments.

How-to Guides

Learn how to solve specific problems and implement features with the Sandbox SDK.

API Reference

Explore the complete API documentation for the Sandbox SDK.

Concepts

Learn about the key concepts and architecture of the Sandbox SDK.

Configuration

Learn about the configuration options for the Sandbox SDK.

GitHub Repository

View the SDK source code, report issues, and contribute to the project.

Beta Information

Learn about the Sandbox Beta, current status, and upcoming features.

Pricing

Understand Sandbox pricing based on the underlying Containers platform.

Limits

Learn about resource limits, quotas, and best practices for working within them.

Discord Community

Connect with the community on Discord. Ask questions, share what you're building, and get help from other developers.