--- title: E2B slug: e2b url: "https://toolweight.com/options/e2b" homepage: "https://e2b.dev" categories: sandbox-providers last_verified: 2026-07-23 license: CC-BY-4.0 --- # E2B > Open-source Firecracker sandboxes with Python and TypeScript SDKs for AI agents. E2B was the first company to sell sandboxes specifically to people building AI agents, and it is still the reference implementation. Sandboxes are Firecracker microVMs defined by a Dockerfile-based template system, driven by first-class Python and TypeScript SDKs. The core infrastructure is Apache-licensed and self-hostable, which makes it the only major option here with a credible exit path. ## Identity | | | | --- | --- | | Name | E2B | | Company | E2B | | One-liner | Open-source Firecracker sandboxes with Python and TypeScript SDKs for AI agents. | | Site | https://e2b.dev | | Docs | https://e2b.dev/docs | | Repo | https://github.com/e2b-dev/E2B | | Founded | 2023 | | Funding | Series A | | Open source | Yes | | Licence | Apache-2.0 | | Brand | https://toolweight.com/vendors/E2B | | Compared in | 1 | ## Where it is compared ### [Sandbox providers](https://toolweight.com/compare/sandbox-providers) Ranked **#7 of 20** on default weights. | Field | Value | Confidence | Verified | Source | Note | | --- | --- | --- | --- | --- | --- | | Cold start | 400 ms | Inferred | - | - | Estimate for create-to-first-output from a client in the same region. The vendor times VM boot alone; the SDK round trip adds most of the rest. | | Cold start (claimed) | 200 ms | Vendor-claimed | 2026-01-15 | https://e2b.dev/docs | Marketed as roughly 150-200 ms to start a sandbox. | | Isolation | microvm | Vendor-claimed | 2026-01-15 | https://e2b.dev/docs | Firecracker. | | Root in guest | ● | Vendor-claimed | 2026-01-15 | https://e2b.dev/docs | - | | Egress control | open | Inferred | - | - | Full outbound by default; no documented per-sandbox allowlist. | | Max runtime | 1440 min | Vendor-claimed | 2026-01-15 | https://e2b.dev/docs/sandbox | Default timeout is 5 minutes, extendable to 24 h on paid plans. | | Persistent FS | ◐ | Inferred | - | - | Filesystem survives pause/resume; there is no durable volume to reattach to a fresh sandbox. | | Snapshot & fork | ◐ | Inferred | - | - | Pause and resume are stable; forking a paused sandbox is newer. | | Custom images | ● | Vendor-claimed | 2026-01-15 | https://e2b.dev/docs/sandbox-template | Templates are Dockerfiles built by the E2B CLI. | | GPU | ○ | Inferred | - | - | - | | Runtimes | python, javascript-typescript, bash, any-oci-image | Inferred | - | - | - | | Preview URLs | ● | Vendor-claimed | 2026-01-15 | https://e2b.dev/docs | getHost(port) returns a public hostname. | | Browser inside | ● | Vendor-claimed | 2026-01-15 | https://github.com/e2b-dev/desktop | The E2B Desktop SDK ships a Chromium image with a stream. | | File up/download | ● | Vendor-claimed | 2026-01-15 | https://e2b.dev/docs | - | | Sydney region | ○ | Inferred | - | - | US and EU regions only. | | Concurrent limit | 100 sandboxes | Inferred | - | - | Approximate paid-tier default; the free tier is far lower and enterprise is negotiable. | | MCP server | ◐ | Community-reported | - | - | Several community MCP servers wrap the SDK; no single canonical first-party one. | | SDKs | python, typescript, cli | Inferred | - | - | - | | Streaming output | ● | Vendor-claimed | 2026-01-15 | https://e2b.dev/docs | - | | Price / hour | $0.17 /hr | Inferred | - | - | Approximate: 2 vCPU + 4 GB at published per-second vCPU and RAM rates. Paid tiers also carry a monthly base fee. | | Meter | per-second | Vendor-claimed | 2026-01-15 | https://e2b.dev/pricing | - | | Idle cost | storage-only | Inferred | - | - | Paused sandboxes bill snapshot storage. | | GitHub stars | 9,000 | Community-reported | - | - | e2b-dev/E2B, rounded. | | Funding | series-a | Community-reported | 2026-07-23 | https://www.insightpartners.com/ideas/e2b-raises-a-21m-series-a-to-offer-cloud-for-ai-agents-to-fortune-100/ | $21M Series A led by Insight Partners, announced July 2025. Announced by the lead investor rather than E2B, hence community rather than vendor-claimed. | | Shipped | 2023 | Inferred | - | - | - | | Positioning | Open-source infrastructure for running AI-generated code. | Inferred | - | - | - | **Verdict.** Still the safest default: the SDKs are the most complete, templates are just Dockerfiles, and the Apache licence means a bad pricing decision by E2B is an inconvenience rather than a migration. It is no longer the fastest, and the monthly base fee makes it a poor fit for hobby-scale traffic. ## Alternatives - [ascii](https://toolweight.com/options/ascii), Agent orchestration over Telegram, running on box's VM infrastructure. - [Blaxel](https://toolweight.com/options/blaxel), Agent-first cloud claiming ~25 ms microVM boots from snapshots. - [box](https://toolweight.com/options/box), Persistent Linux VMs with SSH, per-VM IPv4 and disk-level forking, priced flat. - [Cloudflare Sandbox](https://toolweight.com/options/cloudflare-sandbox), Container sandboxes driven from a Worker, addressed through Durable Objects. - [CodeSandbox SDK](https://toolweight.com/options/codesandbox-sdk), Firecracker VMs with memory snapshots, from the online IDE, now owned by Together AI. - [Daytona](https://toolweight.com/options/daytona), Sub-second container sandboxes for agent workloads, from a team that built a dev-env manager. - [Self-hosted Firecracker](https://toolweight.com/options/diy-firecracker), The baseline: Firecracker on your own metal, plus every hard part you now own. - [exe.dev](https://toolweight.com/options/exe-dev), Persistent VMs you SSH into, with root, apt and systemd, on a flat monthly plan. - [Fly.io Machines](https://toolweight.com/options/fly-machines), Raw Firecracker microVMs with a REST API, durable volumes and 35+ regions. - [Freestyle](https://toolweight.com/options/freestyle), Run untrusted JavaScript and full dev servers, with git hosting and domains built in. - [GitHub Codespaces](https://toolweight.com/options/github-codespaces), Devcontainer-backed cloud VMs built for humans, occasionally repurposed for agents. - [Islo](https://toolweight.com/options/islo), Per-agent isolated cloud sandboxes with enterprise policy controls, from Incredibuild. ## 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/options/e2b - Machine-readable: https://toolweight.com/options/e2b.md · https://toolweight.com/api/v1 · https://toolweight.com/mcp - toolweight takes no affiliate revenue and sells no placements. 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