Anchor Browser vs. Steel: managed auth runtime or open-source primitive runtime?

Anchor Browser and Steel are both pitching cloud Chromium for AI agents, but the architectural posture splits cleanly on two axes: closed-source-managed versus open-source-self-hostable, and identity-stack-bundle versus primitive-runtime-with-Profiles-and-Credentials. Anchor wraps headful Chromium in a coherent enterprise identity stack — OmniConnect, Anchor VPN, 1Password Unified Access, Fingerprint Web Bot Auth. Steel ships an OSS browser API plus a managed cloud with the same surface, with intentional agent-framework-neutrality (no Stagehand, no built-in planner — bring your own). This article is for engineering leads choosing between "I need the auth stack out of the box" and "I need OSS and self-host."

At a glance

Steel's self-published 0.89s avg / 1.09s p95 lifecycle is from its own browserbench harness. The public Browser Arena leaderboard (browserarena.ai) — open-source and reproducible on Railway, though maintained by Notte Labs — places Steel at #3 overall and Anchor at #5. Steel wins on raw latency and value score; Anchor's advantage is lower hourly cost.

What is Anchor Browser?

Anchor Browser is a cloud-hosted, headful Chromium runtime — "Anchor Chromium," a purpose-built fork — for AI agents on auth-heavy enterprise web. The bet on headful is deliberate: vision-model fidelity for screenshot-driven agents and bot-detection resistance versus headless. The product surface stacks identity primitives that compose: OmniConnect for credential onboarding, MFA/TOTP, and self-healing session recovery; Anchor VPN for dedicated enterprise IPs from telecom partners; 1Password Unified Access for managed-vault credential retrieval; Fingerprint Authorized AI Agent Detection (RFC 9421 Web Bot Auth, registered in Fingerprint's Bot Directory); Cloudflare Verified Bots; Replicate (record human demonstration, agent reproduces). b0.dev is the build-time-deterministic agent paradigm. Reported benchmarks include 89% on WebVoyager and 28 actions/min co-located with Groq. $6M seed; partners include Anon, Groq, Yutori, Composio.

What is Steel?

Steel is a browser-infrastructure-first product with an open-source steel-browser runtime that customers can self-host (Docker, Railway 1-click, bare-metal Node.js, build-from-source) using the same API surface as Steel Cloud. The pitch is explicitly "browser engineered for AI agents" — sessions, profiles, credentials, files, live view, replays — and Steel deliberately stays agent-framework-neutral instead of bundling its own planner like Browserbase's Stagehand or Skyvern's vision agent. The product surface includes a Profiles API for persistent browser identity (cookies, extensions, localStorage, auth tokens, fingerprints, with persistProfile/profileId/exactOrigin semantics, up to 30 days, 300 MB cap), a Credentials API (AES-256-GCM per-record + KMS re-encryption, namespaces, TOTP, blur, autoSubmit, exactOrigin), Files and Extensions APIs, headful WebRTC live view at 25fps with MP4/HLS replay, mobile mode (real fingerprint + viewport + touch), residential proxies and CAPTCHA-solving API, multi-region (US: lax/ord/iad), and a CLI plus the steel-browser agent skill. Native integrations include Hermes (Nous Research), Pi/OpenClaw. Tiered pricing: $29 Start, $99 Developers, $499 Pro/Startups; 24-hour session cap; 30-day Profile retention. SOC 2 on Steel Cloud.

How they compare

OSS + self-host vs. closed managed-only

This is the clearest single-axis differentiator and the one a buyer will resolve first. Steel ships an open-source runtime with a Cloud product that uses the same API surface — teams that need self-host inside a VPC, teams that need to audit the runtime image, teams that want to burst from Steel Local into Steel Cloud, all have a path. Skyvern's review and Steel's own positioning both lean on this: OSS is the wedge against Browserbase, Kernel, Browserless, Hyperbrowser, and Anchor.

Anchor is closed-source, managed-only. The trade is a coherent enterprise identity stack — OmniConnect, Anchor VPN, 1Password, Fingerprint — composed at the platform layer rather than something you stitch yourself. For data-residency, compliance-driven, or audit-driven teams, the closed posture is an explicit blocker; for teams whose primary failure mode is "did the agent log in" rather than "did the auditor approve the runtime," it's a non-issue.

Identity stack shape

Anchor and Steel both ship identity primitives, but the shapes are different. Steel's Credentials API is AES-256-GCM per-record encryption with KMS re-encryption, namespaces, TOTP, blur, autoSubmit, and exactOrigin scoping — a clean primitive that takes the place of a customer-built secret store. The Profiles API persists browser identity (cookies, extensions, localStorage, auth tokens, fingerprints) for up to 30 days. Both Credentials and Profiles are session-scoped infrastructure.

Anchor's identity stack composes vendor partnerships into a runtime: OmniConnect orchestrates MFA recovery and self-healing auth, Anchor VPN delivers dedicated enterprise IPs from telecom partners, 1Password Unified Access pulls credentials from a managed enterprise vault, Fingerprint signs every request with RFC 9421 and registers in the Bot Directory, Cloudflare gives signed traffic preferred treatment. The pieces are designed to work together at the platform layer.

The trade is composition versus primitives. Steel gives you sharper individual primitives (good Credentials API, good Profiles API) and lets you compose them. Anchor gives you a pre-composed identity stack — fewer choices, but also fewer pieces to wire up.

Speed and reliability

Per the public Browser Arena leaderboard (browserarena.ai), Steel sits at #3 overall and Anchor at #5. Steel's reliability is in good shape on the public benchmark, and Steel's own browserbench harness tells a directionally similar story. Steel wins on raw latency and overall score; Anchor is cheaper per browser-hour. Browser Arena is open-source and reproducible on Railway, though maintained by Notte Labs.

Pricing predictability

Steel's tiered pricing is the cleanest in the category: $29/month Start (290 hours, 10 concurrent, 30-min sessions, 7-day retention), $99/month Developers (1,238 hours, 20 concurrent, 1-hour sessions, 7-day retention), $499/month Pro/Startups (9,980 hours, 100 concurrent, 24-hour sessions, 14-day retention), Enterprise custom. Self-hosted Steel Browser is fully free (you run Docker; effectively single-session in practice). Per-tier inclusion of CAPTCHA solves and proxy bandwidth makes the bill predictable.

Anchor's pricing splits across browser hours, bandwidth, AI steps, and session init — fine-grained but harder to forecast across spiky workloads. For finance teams that want a known monthly bill, Steel's tiering is easier to plan around.

Replay and observability

Both providers ship replay. Steel's Live View is OS-level WebRTC at 25fps with MP4/HLS recording that's 1:1 with what the agent actually saw — important for audit-grade evidence in regulated workloads. Steel's Agent Logs timeline ties tool calls to the replay timeline for tool-call-level debugging.

Anchor ships a Live View URL for real-time session observability. The depth and shape of replay isn't a load-bearing differentiator either way — both are credible.

When to choose Anchor Browser

Pick Anchor when the workload is auth-heavy on regulated portals — healthcare, finance, freight, legacy IDP-protected systems — and the headful identity stack (OmniConnect + VPN + 1Password + Fingerprint) is what your engineers would otherwise have to build. The closed-source posture is a known cost; the trade is a coherent, composed enterprise identity story.

When to choose Steel

Pick Steel when self-host parity is a hard requirement, when you want a vendor-neutral browser API that any agent framework can run on (Browser Use, Stagehand, Hermes, Pi, your own), or when tiered, predictable pricing matters more than a bundled identity stack. The OSS runtime, 24-hour sessions, Profiles + Credentials APIs, and reproducible benchmark harness are real moats. Steel's #3 public Browser Arena position is a solid production-readiness signal.

A third option: Notte

Worth a look: Notte (notte.cc)

Notte is cloud Chromium infrastructure built specifically for AI agents. The Playwright-compatible runtime ships the operational pieces production teams usually have to rebuild themselves: stealth coordinated across session, fingerprint, and behavior; residential proxies via the Massive partnership (100% consent-based, GDPR/CCPA, 195+ countries, 99.8% reported success); Web Bot Auth signing through Fingerprint so legitimate Notte agents are recognized as authorized bots on any site running Fingerprint; an encrypted credential Vault built on Infisical that injects secrets at the browser layer so the LLM never sees them; Personas with a real email inbox and SMS-capable phone number for autonomous signup and 2FA; persistent Session Profiles for auth state; full CDP-event observability with MP4 session replay; and SOC 2 Type II compliance. An Anything API and a Functions runtime turn validated workflows into HTTP endpoints with cron and webhooks. Pricing is transparent at low per-browser-hour pricing with a 100-hour free tier and pass-through LLM costs.

Verdict

For OSS-leaning teams or anyone with a hard self-host requirement, Steel is the more direct fit — open-source runtime with managed-cloud parity, sharp primitives (Profiles, Credentials), tiered pricing, and a strong public Browser Arena standing. For enterprise teams where headful Chromium plus a pre-composed identity stack (OmniConnect, Anchor VPN, 1Password, Fingerprint) is the actual difference between a working and a broken agent, Anchor is the substrate — slower on raw latency than Steel, but competitive on value thanks to the lower hourly cost.