---
title: CodeSandbox SDK
slug: codesandbox-sdk
url: "https://toolweight.com/tools/codesandbox-sdk"
homepage: "https://codesandbox.io/docs/sdk"
categories: sandbox-providers
last_verified: 2026-11-07
dataset_version: 0738be72
license: CC-BY-4.0
---

# CodeSandbox SDK

> Firecracker VMs with memory snapshots, from the online IDE, now owned by Together AI.

- Years of making browser IDEs resume instantly, now sold directly as SDK infrastructure
- microVMs that hibernate to a memory snapshot, resume with processes intact, and fork cheaply
- Acquired by Together AI in 2025
- The most mature snapshot-and-fork model here; pricing is credit-based, not hourly

## Identity

|  |  |
| --- | --- |
| Name | CodeSandbox SDK |
| Company | Together AI |
| One-liner | Firecracker VMs with memory snapshots, from the online IDE, now owned by Together AI. |
| Site | https://codesandbox.io/docs/sdk |
| Docs | https://codesandbox.io/docs/sdk |
| Founded | 2017 |
| Funding | Acquired |
| Compared in | 1 |

## Where it is compared

### [Sandbox providers](https://toolweight.com/compare/sandbox-providers)
Ranked **#8 of 19** on default weights.
| Field | Value | Confidence | Verified | Source | Note | Permalink |
| --- | --- | --- | --- | --- | --- | --- |
| Cold start | 1.2s | Inferred | - | - | Estimate for a cold create. The vendor's ~1 s figure is a different operation, resuming an existing hibernated VM, so the near-parity between the two columns here is the least defensible estimate on the page: every other provider whose claim describes a snapshot restore lands 2-20× above it. Flagged rather than adjusted, because moving the number to fit the pattern would be inventing one. The harness settles this row first. | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--cold_start_measured |
| Cold start (claimed) | 1s | Vendor-claimed | 2026-01-15 | https://codesandbox.io/docs/sdk | Marketed as resuming a hibernated VM in about a second, processes intact. | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--cold_start_claimed |
| Isolation | microvm | Vendor-claimed | 2026-01-15 | https://codesandbox.io/docs/sdk | Firecracker. | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--isolation_tech |
| Root in guest | ● | Inferred | - | - | - | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--root_access |
| Egress control | open | Inferred | - | - | - | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--egress_control |
| Max runtime | 24h | Inferred | - | - | VMs hibernate on an inactivity timeout rather than hitting a hard runtime cap. | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--max_runtime |
| Persistent FS | ● | Vendor-claimed | 2026-01-15 | https://codesandbox.io/docs/sdk | Disk and memory both persist across hibernation. | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--persistent_fs |
| Snapshot & fork | ● | Vendor-claimed | 2026-01-15 | https://codesandbox.io/docs/sdk | The most mature memory-snapshot-and-fork implementation in this roster. | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--snapshot_fork |
| Custom images | ● | Inferred | - | - | Docker-based environment definitions. | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--custom_images |
| GPU | ○ | Inferred | - | - | - | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--gpu |
| Runtimes | python, javascript-typescript, bash, any-oci-image | Inferred | - | - | - | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--language_runtimes |
| Preview URLs | ● | Vendor-claimed | 2026-01-15 | https://codesandbox.io/docs/sdk | - | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--preview_urls |
| Browser inside | ◐ | Inferred | - | - | - | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--browser_in_sandbox |
| File up/download | ● | Vendor-claimed | 2026-01-15 | https://codesandbox.io/docs/sdk | - | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--file_transfer_api |
| Sydney region | ○ | Inferred | - | - | US and EU clusters. | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--sydney_region |
| Concurrent limit | 100 sandboxes | Inferred | - | - | Tier-dependent; approximate. | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--max_concurrency |
| MCP server | ○ | Inferred | - | - | - | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--mcp_server |
| SDKs | typescript, python | Inferred | - | - | - | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--sdk_languages |
| Streaming output | ● | Vendor-claimed | 2026-01-15 | https://codesandbox.io/docs/sdk | - | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--streaming_stdout |
| Price / hour | $0.15/hr | Vendor-claimed | 2026-11-07 | https://codesandbox.stream/pricing | - | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--price_per_hour |
| Meter | per-second | Inferred | - | - | Credits are consumed while a VM is awake. | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--billing_granularity |
| Idle cost | storage-only | Inferred | - | - | Hibernated VMs stop consuming compute credits. | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--idle_billing |
| GitHub stars | 13,000 | Community-reported | - | - | codesandbox/codesandbox-client, rounded, the IDE, not the SDK. | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--github_stars |
| Funding | acquired | Community-reported | - | - | Acquired by Together AI in 2025. | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--funding_stage |
| Shipped | 2024 | Inferred | - | - | - | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--launched |
| Positioning | The VM infrastructure behind CodeSandbox, sold as an SDK. | Inferred | - | - | - | https://toolweight.com/compare/sandbox-providers#codesandbox-sdk--positioning |

**Verdict.** The best-engineered snapshot-and-fork here for branching workloads, now a component of Together AI rather than its own product.

## Alternatives

- [Blaxel](https://toolweight.com/tools/blaxel), Agent-first cloud claiming ~25 ms microVM boots from snapshots.
- [boat](https://toolweight.com/tools/boat), Persistent Ubuntu VMs for agents with SSH, Docker and disk-level fork, billed per second.
- [Cloudflare Sandbox](https://toolweight.com/tools/cloudflare-sandbox), Container sandboxes driven from a Worker, addressed through Durable Objects.
- [Daytona](https://toolweight.com/tools/daytona), Sub-second container sandboxes for agent workloads, from a team that built a dev-env manager.
- [Self-hosted Firecracker](https://toolweight.com/tools/diy-firecracker), The baseline: Firecracker on your own metal, plus every hard part you now own.
- [E2B](https://toolweight.com/tools/e2b), Open-source Firecracker sandboxes with Python and TypeScript SDKs for AI agents.
- [exe.dev](https://toolweight.com/tools/exe-dev), Persistent VMs you SSH into, with root, apt and systemd, on a flat monthly plan.
- [Fly.io Machines](https://toolweight.com/tools/fly-machines), Raw Firecracker microVMs with a REST API, durable volumes and 35+ regions.
- [Freestyle](https://toolweight.com/tools/freestyle), Run untrusted JavaScript and full dev servers, with git hosting and domains built in.
- [GitHub Codespaces](https://toolweight.com/tools/github-codespaces), Devcontainer-backed cloud VMs built for humans, occasionally repurposed for agents.
- [Islo](https://toolweight.com/tools/islo), Per-agent isolated cloud sandboxes with enterprise policy controls, from Incredibuild.
- [Modal](https://toolweight.com/tools/modal), Serverless Python compute with a Sandbox API bolted onto a GPU-first platform.

## Logo & brand colours

SVG files: https://toolweight.com/teams/codesandbox/logo.svg and https://toolweight.com/teams/codesandbox/mono.svg. JSON: https://toolweight.com/api/v1/brands/codesandbox.

| Hex | oklch |
| --- | --- |
| #dcff50 | oklch(94.4% 0.196 120.2) |

## Licence and attribution

Data from Toolweight (https://toolweight.com), licensed CC-BY-4.0.

- Licence: [CC-BY-4.0](https://creativecommons.org/licenses/by/4.0/)
- Canonical HTML: https://toolweight.com/tools/codesandbox-sdk
- Machine-readable: https://toolweight.com/tools/codesandbox-sdk.md · https://toolweight.com/api/v1 · https://toolweight.com/mcp
- Toolweight takes no affiliate revenue and sells no placements.