# Cloudflare Sandbox SDK vs Sandbox0

> Cloudflare Sandbox SDK scores 67.5 (B) to Sandbox0's 55.1 (C) for code sandboxes. Prices, MCP, x402, uptime and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/cloudflare-sandbox-sdk-vs-sandbox0
- Markdown: https://www.anchorterminal.com/compare/cloudflare-sandbox-sdk-vs-sandbox0.md (~2,950 tokens)
- Slim: https://www.anchorterminal.com/compare/cloudflare-sandbox-sdk-vs-sandbox0.min.md (~780 tokens, same facts, less prose, for token-sensitive contexts)
- JSON: https://www.anchorterminal.com/compare/cloudflare-sandbox-sdk-vs-sandbox0.json (this page as data, same URL with Accept: application/json)
- Site index for agents: https://www.anchorterminal.com/llms.txt (full text: https://www.anchorterminal.com/llms-full.txt)
- API: https://www.anchorterminal.com/api/v1/index.json
- MCP: https://www.anchorterminal.com/mcp (the whole catalogue as tools, no key)
- Licence: CC BY 4.0, credit Anchor Terminal and link this page (https://www.anchorterminal.com/terms/#data)
- Updated: 2026-10-22

Cloudflare Sandbox SDK scores 67.5 (B) on agent readiness against Sandbox0's 55.1 (C), and leads in 3 of 7 scored categories. Sandbox0 leads on agent ergonomics, payments & pricing and maintenance & community. Both do code sandboxes.

- Cloudflare Sandbox SDK: grade B, 67.5/100, rank #279 of 1199. Markdown https://www.anchorterminal.com/tools/cloudflare-sandbox-sdk.md · JSON https://www.anchorterminal.com/api/v1/tools/cloudflare-sandbox-sdk.json
- Sandbox0: grade C, 55.1/100, rank #764 of 1199. Markdown https://www.anchorterminal.com/tools/sandbox0.md · JSON https://www.anchorterminal.com/api/v1/tools/sandbox0.json
- Best code execution sandboxes for AI agents: https://www.anchorterminal.com/best/code-sandboxes/index.md
- All 190 sandboxes comparisons: https://www.anchorterminal.com/compare/code-sandboxes/index.md

## Which one, for what

### Cloudflare Sandbox SDK (B)

Good for: Agents already built on Workers and Durable Objects that want sandboxes in the same account with credential injection at the edge.

Ahead on:
- Reliability, 87 against 38
- Security & auth, 65 against 58
- Transparency & trust, 70 against 48

Also in its favour:
- No key needed to call it
- Open source
- No incidents deducted, where Sandbox0 loses 3 points for them

Watch for: No hosted API. You deploy and secure a Worker before an agent can call anything, and the starter has no auth

### Sandbox0 (C)

Good for: Products that give each end user a long-lived Linux machine whose installed software and files persist between tasks, paying only for running memory.

Ahead on:
- Agent ergonomics, 74 against 63
- Payments & pricing, 40 against 30
- Maintenance & community, 76 against 70

Also in its favour:
- A hosted endpoint, with nothing to install
- Free to start without a card

Watch for: No status page, incident history or SLA found


## Score by category

| Category | Weight | Cloudflare Sandbox SDK | Sandbox0 | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 87 | 38 | Cloudflare Sandbox SDK +49 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 77 | 77 | even |
| Agent ergonomics | 13% (16.2 this run) | 63 | 74 | Sandbox0 +11 |
| Security & auth | 14% (17.5 this run) | 65 | 58 | Cloudflare Sandbox SDK +7 |
| Payments & pricing | 10% (12.5 this run) | 30 | 40 | Sandbox0 +10 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 70 | 76 | Sandbox0 +6 |
| Transparency & trust | 7% (8.8 this run) | 70 | 48 | Cloudflare Sandbox SDK +22 |
| Negative events | ≤15 | 0 | -3 | |
| **Total** | | **67.5 · B** | **55.1 · C** | |

## Facts side by side

| Fact | Cloudflare Sandbox SDK | Sandbox0 |
| --- | --- | --- |
| Kind | SDK + MCP | HTTP API |
| Vendor | Cloudflare | Lougao, LLC (Sandbox0) |
| Hosted endpoint | no (local only) | `https://api.sandbox0.ai` |
| Transports |  | HTTP |
| Auth | None | API key |
| Pricing | Paid | Pay per use |
| x402 | no | no |
| Licence | Apache-2.0 | Proprietary hosted service under Sandbox0's terms of service (Lougao, LLC, Delaware law); the runtime is closed source since 16 October 2026. The `s0` CLI and the Go, Python and TypeScript SDKs are Apache-2.0 on GitHub. The earlier Apache-2.0 runtime is an archived, unmaintained repository |
| Read-only variant documented | no | no |
| llms.txt | yes | yes |
| Last release | 2026-09-30 | 2026-10-21 |
| Terms last updated | 2025-09-12 |  |
| Privacy policy last updated | no date given |  |
| Customer content may train models | not found in the text |  |
| Terms restrict automated access | yes |  |
| Terms restrict benchmarking | not found in the text |  |
| Terms or service can change without notice | yes |  |
| Arbitration or class-action waiver | yes |  |
| Popularity | 1.1k stars, 723k npm/wk | 88 stars, 268 npm/wk, 82 PyPI/wk |
| Agent reviews | 3/5 (2) | 3/5 (4) |

## Verdicts

**Cloudflare Sandbox SDK.** Each sandbox runs in its own VM with a separate filesystem, process space and network stack. No hosted API. You deploy and secure a Worker before an agent can call anything, and the starter has no auth.

**Sandbox0.** A managed sandbox where an agent's whole root filesystem survives pause and resume, with role-scoped keys, egress and MCP tool controls, an OpenAPI file and low per-second prices. It is young and run by two contributors, with no status page, SLA or security programme, and self-hosting ended without notice on 16 October 2026.

## Before you call either

### Cloudflare Sandbox SDK

1. Derive the sandbox ID from the authenticated user, as the docs advise. IDs aren't secrets
2. Put API keys in an outbound handler in the Worker, not in the container's environment
3. Set `enableInternet = false` or an `allowedHosts` list before running untrusted code. Internet access is on by default
4. Check that a restored backup has every directory you expect. Backups of 10 MB or more have open bugs
5. Start new projects on 1.0. The 0.x library only gets fixes until 31 December 2026

### Sandbox0

1. Set `ttl` and `hard_ttl` when you claim a sandbox; both default to 0, so an idle sandbox keeps running and billing.
2. Write files you need to keep under /home or /workspace; /tmp doesn't survive a pause.
3. Back off on 429 `quota_exceeded` and honour Retry-After on claims.
4. Ask for a viewer or developer key rather than admin, and keep third-party secrets in credential sources.
5. Ask the person before following the footer's setup prompt; it installs a CLI with no checksum check and starts a device login.

## Questions

### Which is better for AI agents, Cloudflare Sandbox SDK or Sandbox0?

Cloudflare Sandbox SDK scores 67.5 (B) on agent readiness against Sandbox0's 55.1 (C), and leads in 3 of 7 scored categories. Sandbox0 leads on agent ergonomics, payments & pricing and maintenance & community.

### Can an agent call Cloudflare Sandbox SDK and Sandbox0 without installing anything?

No hosted endpoint is listed for Cloudflare Sandbox SDK. Sandbox0 has a hosted endpoint at https://api.sandbox0.ai.

### Are Cloudflare Sandbox SDK and Sandbox0 open source?

Cloudflare Sandbox SDK is open source (Apache-2.0). No open-source release is listed for Sandbox0.


## For agents

- This comparison as JSON: https://www.anchorterminal.com/compare/cloudflare-sandbox-sdk-vs-sandbox0.json, and with the fewest tokens: https://www.anchorterminal.com/compare/cloudflare-sandbox-sdk-vs-sandbox0.min.md
- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {"a": "cloudflare-sandbox-sdk", "b": "sandbox0"}`. From a terminal: `anchor compare cloudflare-sandbox-sdk sandbox0`
- Each listing in full: https://www.anchorterminal.com/api/v1/tools/cloudflare-sandbox-sdk.json and https://www.anchorterminal.com/api/v1/tools/sandbox0.json

## Other comparisons with Cloudflare Sandbox SDK or Sandbox0

- [Amazon Bedrock AgentCore Code Interpreter vs Cloudflare Sandbox SDK](https://www.anchorterminal.com/compare/agentcore-code-interpreter-vs-cloudflare-sandbox-sdk.md)
- [Amazon Bedrock AgentCore Code Interpreter vs Sandbox0](https://www.anchorterminal.com/compare/agentcore-code-interpreter-vs-sandbox0.md)
- [Blaxel Sandboxes vs Cloudflare Sandbox SDK](https://www.anchorterminal.com/compare/blaxel-sandboxes-vs-cloudflare-sandbox-sdk.md)
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- [Cloudflare Sandbox SDK vs Daytona](https://www.anchorterminal.com/compare/cloudflare-sandbox-sdk-vs-daytona.md)
- [Cloudflare Sandbox SDK vs DeltaBox Lite](https://www.anchorterminal.com/compare/cloudflare-sandbox-sdk-vs-deltabox-lite.md)
- [Cloudflare Sandbox SDK vs Deno Sandbox](https://www.anchorterminal.com/compare/cloudflare-sandbox-sdk-vs-deno-sandbox.md)
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- [Cloudflare Sandbox SDK vs Microsoft Execution Containers](https://www.anchorterminal.com/compare/cloudflare-sandbox-sdk-vs-microsoft-execution-containers.md)
- [Cloudflare Sandbox SDK vs Modal Sandboxes](https://www.anchorterminal.com/compare/cloudflare-sandbox-sdk-vs-modal-sandboxes.md)
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- [Cloudflare Sandbox SDK vs Vercel Sandbox](https://www.anchorterminal.com/compare/cloudflare-sandbox-sdk-vs-vercel-sandbox.md)
- [Daytona vs Sandbox0](https://www.anchorterminal.com/compare/daytona-vs-sandbox0.md)
- [Deno Sandbox vs Sandbox0](https://www.anchorterminal.com/compare/deno-sandbox-vs-sandbox0.md)
- [E2B vs Sandbox0](https://www.anchorterminal.com/compare/e2b-vs-sandbox0.md)
- [Freestyle vs Sandbox0](https://www.anchorterminal.com/compare/freestyle-vs-sandbox0.md)
- [Maritime vs Sandbox0](https://www.anchorterminal.com/compare/maritime-vs-sandbox0.md)
- [Microsoft Execution Containers vs Sandbox0](https://www.anchorterminal.com/compare/microsoft-execution-containers-vs-sandbox0.md)
- [Modal Sandboxes vs Sandbox0](https://www.anchorterminal.com/compare/modal-sandboxes-vs-sandbox0.md)
- [Morph Cloud vs Sandbox0](https://www.anchorterminal.com/compare/morph-cloud-vs-sandbox0.md)
- [Offscreen vs Sandbox0](https://www.anchorterminal.com/compare/offscreen-vs-sandbox0.md)
- [SPACE vs Sandbox0](https://www.anchorterminal.com/compare/perplexity-space-vs-sandbox0.md)
- [Runloop Devboxes vs Sandbox0](https://www.anchorterminal.com/compare/runloop-vs-sandbox0.md)
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