The Top 5 Sandboxes for Claude Code

Claude Code is not a normal CLI.

It reads files, edits projects, runs shell commands, starts servers, installs dependencies, resumes conversations, calls tools, and sometimes works unattended with fewer permission prompts. Anthropic's own sandbox environment docs make the core point: isolation matters most when Claude Code is allowed to work with fewer prompts, run unattended, or touch code you do not fully trust.

That is why "Claude Code sandbox" is a sharper search than "code execution sandbox." The question is not only whether a provider can run claude -p. Many can. The question is whether the sandbox can become the safe development computer where Claude Code does real work.

This ranking compares five platforms by the needs that show up once Claude Code becomes part of a product:

• a real shell and filesystem
• package installation and native dependencies
• long-running dev servers and background processes
• interactive or reattachable terminal sessions
• preview URLs for generated apps
• branchable, reviewable source code
• an isolation boundary that still lets humans debug

By that standard, Freestyle VMs are the clear winner. Freestyle VMs are the most powerful VMs for AI agents: they are hardware-virtualized, they run real Linux, and they can run forever when configured to stay running.

1. Freestyle VMs

Freestyle VMs are the best Claude Code sandbox because they treat Claude Code like what it is: a coding agent that needs a computer.

The Freestyle Claude Code guide shows the exact product shape. You can build a VM snapshot with Claude Code installed, run one-off prompts with vm.exec(), run autonomous tasks as a non-root Linux user, attach an interactive Claude Code terminal over the PTY API, and bridge the Claude Agent SDK so your orchestration code runs outside the VM while Claude Code executes inside it.

That matters because Claude Code work is stateful. The agent may install a package, start a dev server, answer an onboarding prompt, write a CLAUDE.md, inspect a failing test, and keep a terminal UI open while the user closes their browser tab. A request/response command runner can fake some of that. A real VM can just host it.

Freestyle's PTY sessions are especially important for Claude Code. They are long-lived interactive shells inside the VM that can be attached, detached, and reattached over WebSocket. They survive client disconnects, VM suspends, and VM forks. That makes a Claude Code terminal a product surface, not just a stream of logs.

The rest of the VM model fits the same shape. The VM lifecycle docs describe VMs as durable runtime objects: create them, stop them, start them again, resize them, fork them from current running state, and delete them when the workspace is finished. Set idleTimeoutSeconds to null for workloads that should stay running until you explicitly stop or delete them.

Claude Code also needs previews. Freestyle VM domains route HTTPS traffic from a hostname to a port inside the VM, with free *.style.dev preview domains. If Claude Code starts a Next.js app, Vite server, Rails app, documentation site, or custom HTTP service, your product can expose the port without inventing a preview abstraction.

Humans still need an escape hatch. Freestyle SSH access uses scoped identities and tokens, including access as specific Linux users. That means a developer, support engineer, or internal tool can debug the same machine Claude Code is using, while your product keeps API keys server-side.

Finally, Claude Code output has to be reviewed. The VM is the live workspace, but source code should still live in a repository with branches, diffs, and review. If your product needs Git infrastructure for agent-generated code, use Freestyle Git next to Freestyle VMs: Git for source of truth, VMs for the running computer.

Freestyle wins because it does not reduce Claude Code to "run this command and return stdout." It gives Claude Code a real Linux machine, persistent terminals, ports, SSH, snapshots, forks, and the ability to keep working for as long as the product needs.

2. Blaxel

Blaxel has one of the strongest Claude Code-specific stories outside Freestyle. Its tutorial shows Claude Code running inside a Blaxel sandbox to execute coding tasks on a hosted codebase, with persistent storage and secure network access.

Blaxel's broader sandbox overview is also credible for agent products. It describes lightweight sandboxed virtual machines with filesystem and process APIs, sub-25ms cold starts, managed standby, process and filesystem state restoration, volumes, exposed ports, log streaming, MCP support, and examples like code review agents and code generation agents.

That makes Blaxel a strong choice when you want a broader agent platform around sandboxes, model gateway, hosted agents, MCP servers, and managed lifecycle. It is built for agentic applications, not only short code snippets.

Freestyle ranks higher for Claude Code workspaces because the primitive is simpler and more complete: a hardware-virtualized Linux VM that your product owns as the workspace. The Freestyle model puts PTYs, SSH, ports, lifecycle, forks, Linux users, and long-running state at the center. Blaxel is compelling when you want a managed agent platform; Freestyle is stronger when the Claude Code sandbox needs to be the user's durable computer.

3. E2B

E2B's Claude Code docs are direct and useful. E2B provides a pre-built claude template, supports running Claude Code headless, cloning repositories, streaming JSON output, resuming Claude Code sessions, writing project context files, and connecting MCP tools.

That is a very good fit for product teams that want Claude Code as an isolated tool inside an agent loop. If the job is "start a sandbox, clone a repo, run Claude Code, collect the diff, kill the sandbox," E2B has a mature path.

The limitation is not that E2B cannot run Claude Code. It clearly can. The question is what happens when the sandbox becomes a shared product workspace. Claude Code often needs a live terminal, a dev server, a preview, a package manager, a long-running process, and a human debugging path all attached to the same environment.

Freestyle is stronger there because the VM is the product boundary. The Claude Code process, terminal sessions, app server, preview port, SSH access, files, and lifecycle all live in one Linux machine. E2B is excellent for Claude Code execution. Freestyle is better when Claude Code is one actor inside a live development computer.

4. Daytona

Daytona's Claude Code guide shows how to create a sandbox, install Claude Code, run it with --dangerously-skip-permissions, and stream PTY output. That is the right direction for Claude Code because a PTY is often necessary once the CLI behaves like an interactive coding tool instead of a batch command.

Daytona is also a serious sandbox platform for agent work. It has SDKs, sandbox creation, process execution, PTY sessions, and a growing set of agent guides. For teams that want an isolated development environment and a provider with strong agent positioning, Daytona belongs high on the list.

Freestyle still wins for product-shaped Claude Code environments because of the VM lifecycle and workspace model. A Freestyle VM can be kept running indefinitely, exposed through HTTPS domains, debugged through scoped SSH, driven through persistent PTYs, and forked from a running state. Those are the primitives you need when Claude Code is not just doing a task, but sharing a live machine with your product and user.

Choose Daytona when you want a capable sandbox platform with good Claude Code examples. Choose Freestyle when the sandbox has to become a long-lived computer with real Linux semantics and operational escape hatches.

5. Vercel Sandbox

Vercel Sandbox is a natural candidate for teams already building on Vercel. Vercel describes it as a compute primitive for safely running untrusted or user-generated code, with dynamic workloads for AI agents, code generation, developer experimentation, live previews, Firecracker microVM isolation, Node and Python runtimes, package installation, snapshots, and SDK/CLI access.

Vercel also has a Claude Agent SDK sandbox guide that explains why the SDK should run in a sandboxed environment: it executes commands, manages files, and maintains conversational state. The guide walks through installing the Claude Code CLI and Anthropic SDK dependencies in a Vercel Sandbox.

That makes Vercel a good fit when your product is Vercel-native, your generated app previews belong in the Vercel ecosystem, and your Claude Code workload is close to web-app generation.

Freestyle ranks higher because Claude Code's needs are not limited to a web platform integration. A serious coding agent may need arbitrary Linux packages, long-lived terminals, SSH access, private networking, background services, custom daemons, multiple users, and forks of a live workspace. Freestyle keeps those capabilities in one VM abstraction instead of asking the product to split between sandbox execution, preview infrastructure, and debugging workflows.

The ranking at a glance

How to choose

If your Claude Code use case is narrow, pick the narrowest good tool. E2B is strong for running Claude Code as an isolated execution step. Vercel is a good fit for Vercel-native agents. Daytona and Blaxel both have serious agent sandbox stories.

If your Claude Code use case is becoming a product workspace, choose Freestyle.

That is the difference. Claude Code does not only need a place to execute. It needs a machine where code can be installed, edited, served, inspected, debugged, forked, resumed, and reviewed. For that workload, the best Claude Code sandbox is a real VM.