Guide, updated Oct 16, 2026
Best code sandboxes for AI agents
Isolated machines where agents can safely run code. We list 8 code sandboxes, 3 open source. Summaries come from each vendor's own site and every link was checked on or before Oct 16, 2026.
Shortlist
All 8 at a glance
Alphabetical. Nothing in this guide is a paid placement.
| Tool | What it does | Open source | More |
|---|---|---|---|
| Agent 37 | Cloud sandboxes for running AI agents, positioned as lower-cost agent infrastructure. | No | Alternatives |
| AIO Sandbox | All-in-one agent sandbox with browser, shell, file access, VSCode Server, and MCP in one container. | Yes | Alternatives |
| Cloudflare Sandbox SDK | Run untrusted or generated code in Linux VMs or isolated Workers on Cloudflare. | No | Alternatives |
| Daytona | Secure sandboxes for running AI-generated code. | Yes | Alternatives |
| E2B | Isolated cloud machines for agents to run code, browse, and use tools. | Yes | Alternatives |
| Modal | Serverless cloud for running, training, and serving AI workloads, including sandboxes. | No | Alternatives |
| Runloop | Code sandboxes (Devboxes) for AI coding agents, plus evaluations. | No | Alternatives |
| Vercel Sandbox | Isolated Linux microVMs on Vercel for untrusted or agent-generated code. | No | Alternatives |
How to choose
What to check before you pick
- Isolation: microVMs, containers or isolated workers. Untrusted, model-written code needs strong isolation.
- Start time and session length: how fast a sandbox boots and how long it can stay alive.
- What is inside: a shell, file system, browser, or language runtimes your agent needs.
- Hosting: managed cloud, self-hostable open source, or tied to a platform you already use.
- Pricing unit: usually per second or minute of compute. Check each vendor's pricing page.
This checklist is general advice. Check each vendor's docs and pricing page for current details.
The tools
Each option in one paragraph
Agent 37
agent37.comCloud sandboxes for running AI agents, positioned as lower-cost agent infrastructure.
In their words: “Cloud Sandbox for Agents | Agent 37”
AIO Sandbox
sandbox.agent-infra.comAll-in-one agent sandbox with browser, shell, file access, VSCode Server, and MCP in one container.
In their words: “AIO Sandbox”
Cloudflare Sandbox SDK
developers.cloudflare.comRun untrusted or generated code in Linux VMs or isolated Workers on Cloudflare.
In their words: “Overview · Cloudflare Sandboxes docs”
Daytona
daytona.ioSecure sandboxes for running AI-generated code.
In their words: “Daytona - Secure Infrastructure for Running AI-Generated Code”
E2B
e2b.devIsolated cloud machines for agents to run code, browse, and use tools.
In their words: “E2B | The Enterprise AI Agent Cloud”
Modal
modal.comServerless cloud for running, training, and serving AI workloads, including sandboxes.
In their words: “Modal: The platform for production AI”
Runloop
runloop.aiCode sandboxes (Devboxes) for AI coding agents, plus evaluations.
In their words: “Runloop - Your AI Agent Accelerator”
Vercel Sandbox
vercel.comIsolated Linux microVMs on Vercel for untrusted or agent-generated code.
In their words: “Vercel Sandbox”
Head to head
Compare them side by side
FAQ
Questions
Which code sandboxes does Agent Stack Directory list?
8: Agent 37, AIO Sandbox, Cloudflare Sandbox SDK, Daytona, E2B, Modal, Runloop, Vercel Sandbox.
Which of them are open source?
AIO Sandbox, Daytona, E2B are marked open source in our data.
How is this list ordered?
Alphabetically. No placement in this guide is paid. Sponsored and featured tools are labeled elsewhere on the site and never reordered here.
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