Steel alternatives
The 6 alternatives below are grouped by kind of sandbox, and each says what it does differently from Steel. Start from whatever made you look: missing GPUs, session limits, self-hosting, pricing or isolation.
Why teams look beyond Steel
The open-source choice among hosted browser APIs: self-host for free, move to Steel Cloud for stealth, captchas and concurrency.
- Launch plan sessions are capped at 15 minutes; 24-hour sessions need Enterprise
- Isolation boundary and regions are not documented
- Captcha solving, credentials, files and the MCP server are cloud-only
- Compliance certifications were not readable from the trust centre
Steel alternatives, by kind
Browser and desktop sandboxes
Hosted browsers and full desktops that computer-use agents click, type and browse in.
Browserbase
Hosted headless Chromium sessions for web agents, driven over CDP with Playwright, Puppeteer, Selenium or the Stagehand SDK, with Contexts for persisted logins and four regions.
- Isolated Chromium session
How it differs: Web agents that need managed Chromium at scale with persisted logins and stealth. A mature managed-Chromium service for web agents, with strong SDK and framework coverage but an undocumented isolation boundary.
Browserless
Managed headless Chrome, Firefox and WebKit over WebSocket for Puppeteer, Playwright and Selenium, with BrowserQL stealth, REST endpoints and a Docker image you can self-host.
- Not documented
- Open source
- Self-hostable
- GPU
How it differs: Existing Puppeteer, Playwright or Selenium automations that want a managed or self-hosted browser pool. A proven managed browser pool for automation code, less tailored to agents than its newer peers and silent on isolation.
Hyperbrowser
Credit-billed cloud Chrome sessions with profiles, stealth and captcha solving, plus one-shot agent runs (Claude Computer Use, OpenAI CUA, Browser Use) and separate VM-based code sandboxes.
- Isolated browser instance
How it differs: Agents that need cheap browser hours with a built-in path to run computer-use models as one-shot tasks. A credit-priced browser cloud with the broadest built-in agent-model support, held back by thin isolation and compliance documentation.
Kernel
Browsers for agents where each Chromium runs in its own Unikraft unikernel VM, with standby that stops billing, profiles, and open-source images under Apache-2.0.
- Unikernel VM per browser
- Open source
- Self-hostable
- GPU
- Pause/resume
How it differs: Agents that need fast, hypervisor-isolated browsers with pay-only-while-active billing. Hypervisor-isolated browsers with standby billing and open images, the most transparent isolation story among the closed clouds.
Lightpanda
A headless browser written from scratch in Zig (AGPL-3.0) with no graphical rendering, offered as a CDP endpoint on Lightpanda Cloud with a free 10-hour tier.
- Not documented
- Open source
- Self-hostable
How it differs: High-volume page fetching and crawling where memory and speed matter more than pixel-accurate rendering. A fast, frugal engine for machine browsing rather than a visual sandbox; the cloud tier is young and lightly documented.
Notte
Cloud browser sessions at $0.01 per hour with stealth, proxies, profiles, secret vaults and personas, a hosted MCP server and serverless browser functions; SSPL-licensed core.
- Isolated browser instance
- Open source
How it differs: Agents that need cheap browser sessions with credential vaults and synthetic identities for sign-ups and logins. A low-cost browser cloud whose identity and credential tooling stands out, with isolation left undocumented.
Steel vs alternatives
| Sandbox | Isolation | Open source | Self-host / BYOC | Cold start (vendor) | Max session | Snapshots / pause | GPU | SDKs |
|---|---|---|---|---|---|---|---|---|
| Steel | Isolated Chromium session | Yes | Yes / No | Not documented | 15 min / 1 h / 24 h | No / No | No | Python, JavaScript/TypeScript, Go, Rust, CLI, REST API, MCP server |
| Browserbase | Isolated Chromium session | No | No / No | <2 s (claim) | 6 h (15 min Free) | No / No | No | Python, JavaScript/TypeScript, REST API, MCP server |
| Browserless | Not documented | Yes | Yes / No | Not documented | 2 min to 60 min by plan | No / No | Yes | JavaScript/TypeScript, Python, CLI, REST API, MCP server |
| Hyperbrowser | Isolated browser instance | No | No / No | <500 ms (claim) | Up to 12 h | No / No | No | Python, JavaScript/TypeScript, CLI, REST API, MCP server |
| Kernel | Unikernel VM per browser | Yes | Yes / No | ~30 ms p50 (claim) | Up to 72 h | Yes / Yes | Yes | JavaScript/TypeScript, Python, Go, CLI, REST API, MCP server |
| Lightpanda | Not documented | Yes | Yes / No | Not documented | 15 min per connection | No / No | No | CLI, REST API, MCP server |
| Notte | Isolated browser instance | Yes | No / No | Not documented | 15 min to 5 h by plan | No / No | No | Python, JavaScript/TypeScript, CLI, REST API, MCP server |
Frequently asked questions
What are the main alternatives to Steel?
Is there an open-source alternative to Steel?
Cite this page
Agent Sandboxes. (2026). Steel alternatives. agentsandboxes.org. Last reviewed November 9, 2026. https://agentsandboxes.org/alternatives/steel/
Found an error or a missing sandbox? Submit a correction — every entry links to the sources it relies on.