Steel

Open-source cloud browser API with sessions and stealth for AI agents

By Nathan KesslerUpdated Jul 27, 2026

Each tool is evaluated against our methodology using public docs, vendor demos, and hands-on testing.

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What is Steel?

Steel is an open-source, cloud-hosted headless browser API built for AI agents and automated web workflows. It gives you on-demand browser sessions compatible with Puppeteer, Playwright, Selenium, and custom SDKs. Session starts are sub-1-second in the same region, and sessions can run for up to 24 hours. CAPTCHA solving, proxies, and browser-fingerprint anti-detection are built in. The core engine is open source on GitHub with Docker support for self-hosting, and a session viewer with live and recorded (RRweb) replay handles debugging.

Our verdict

Steel fits teams that want an open-source browser API they can self-host via Docker rather than lock into a closed vendor, with CAPTCHA solving and session replay built in for debugging automated runs. Its scale claims (800B+ tokens scraped, 1,000,000+ browser hours) and reported YC/Series A backing are vendor-stated or unconfirmed by primary sources, so treat them as marketing figures rather than audited data.

Categories:

Browser Infrastructure

Browser infrastructure gives you a remote Chrome or Chromium instance over a protocol like CDP or Playwright, so you run automation without managing browser servers. It is the layer many scraping APIs and agent tools build on, and it suits teams that want control of the browser without the operations work.