# Anchor Browser vs Selenium

> Selenium scores 73.6 (BB) to Anchor Browser's 67.3 (B) for browser automation. Prices, MCP, x402, uptime and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/anchor-browser-vs-selenium
- Markdown: https://www.anchorterminal.com/compare/anchor-browser-vs-selenium.md (~2,600 tokens)
- Slim: https://www.anchorterminal.com/compare/anchor-browser-vs-selenium.min.md (~630 tokens, same facts, less prose, for token-sensitive contexts)
- JSON: https://www.anchorterminal.com/compare/anchor-browser-vs-selenium.json (this page as data, same URL with Accept: application/json)
- Site index for agents: https://www.anchorterminal.com/llms.txt (full text: https://www.anchorterminal.com/llms-full.txt)
- API: https://www.anchorterminal.com/api/v1/index.json
- Updated: 2026-10-14

Selenium scores 73.6 (BB) on agent readiness against Anchor Browser's 67.3 (B), and leads in 4 of 7 scored categories. Anchor Browser leads on security & auth. Both do browser automation.

- Anchor Browser: grade B, 67.3/100, rank #269 of 1076. Markdown https://www.anchorterminal.com/tools/anchor-browser.md · JSON https://www.anchorterminal.com/api/v1/tools/anchor-browser.json
- Selenium: grade BB, 73.6/100, rank #90 of 1076. Markdown https://www.anchorterminal.com/tools/selenium.md · JSON https://www.anchorterminal.com/api/v1/tools/selenium.json
- Best browser automation tools for AI agents: https://www.anchorterminal.com/best/browser/index.md
- All 120 browser comparisons: https://www.anchorterminal.com/compare/browser/index.md

## Which one, for what

### Anchor Browser (B)

Good for: Agents that must work inside signed-in accounts, with managed identities, MFA handling and a human sign-in link, and agents that need to start with no human signup.

Ahead on:
- Security & auth, 54 against 43

Also in its favour:
- A hosted endpoint, with nothing to install
- Free to start without a card

Watch for: No service agreement or API terms found. anchorbrowser.io/terms is a website terms of use dated 16 March 2025

### Selenium (BB)

Good for: Agents that write test or automation scripts in any of five languages, and teams with a Grid.

Ahead on:
- Reliability, 90 against 80
- Schema & documentation, 89 against 80
- Maintenance & community, 94 against 57
- Transparency & trust, 74 against 51

Also in its favour:
- Agent-ready, a grade of BB or better
- No key needed to call it
- Open source

Watch for: No MCP server from the project. The docs point to community servers and say they are third-party


## Score by category

| Category | Weight | Anchor Browser | Selenium | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 80 | 90 | Selenium +10 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 80 | 89 | Selenium +9 |
| Agent ergonomics | 13% (16.2 this run) | 73 | 70 | Anchor Browser +3 |
| Security & auth | 14% (17.5 this run) | 54 | 43 | Anchor Browser +11 |
| Payments & pricing | 10% (12.5 this run) | 60 | 60 | even |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 57 | 94 | Selenium +37 |
| Transparency & trust | 7% (8.8 this run) | 51 | 74 | Selenium +23 |
| Negative events | ≤15 | 0 | 0 | |
| **Total** | | **67.3 · B** | **73.6 · BB** | |

## Facts side by side

| Fact | Anchor Browser | Selenium |
| --- | --- | --- |
| Kind | HTTP API | SDK + MCP |
| Vendor | Anchor Forge Inc. | Selenium project (Software Freedom Conservancy) |
| Hosted endpoint | `https://api.anchorbrowser.io` | no (local only) |
| Transports | HTTP | HTTP |
| Auth | OAuth or key | None |
| Pricing | Freemium | Free |
| x402 | no | no |
| Licence | Proprietary cloud service. No service agreement was found, only a website terms of use. The TypeScript and Python SDKs and the self-hosted MCP server are Apache-2.0 | Apache-2.0 |
| Read-only variant documented | no | no |
| llms.txt | yes | yes |
| Last release | 2026-07-28 | 2026-10-09 |
| Terms last updated | no document linked | no document linked |
| Privacy policy last updated | 2026-02-24 | no document linked |
| Customer content may train models |  |  |
| Terms restrict automated access |  |  |
| Terms restrict benchmarking |  |  |
| Terms or service can change without notice |  |  |
| Arbitration or class-action waiver |  |  |
| Popularity | 43k npm/wk, 10k PyPI/wk | 35k stars, 1.8M npm/wk, 6.9M PyPI/wk |

## Verdicts

**Anchor Browser.** The API has a public OpenAPI 3.1 document, per-unit prices and Agent Access, an unauthenticated flow that issues a trial API key without a dashboard account. No service agreement is published, only a website terms of use, and the documented CDP connection puts the API key in the URL.

**Selenium.** Selenium is stable, Apache-2.0 software on 4.51.0 with bindings in five languages, CI passing on trunk, an llms.txt and an agent guide added in September 2026. It has no MCP server of its own, Selenium Manager sends usage statistics by default, and Grid accepts unauthenticated sessions unless a username and password are set.

## Before you call either

### Anchor Browser

1. Send the key in the `anchor-api-key` header. For CDP, build `wss://connect.anchorbrowser.io?apiKey=<key>&sessionId=<id>` and keep that URL out of logs
2. Set `session.timeout.idle_timeout` and `max_duration` and end sessions with DELETE. The default maximum is 180 minutes, and browser time bills by the minute
3. Session creation is capped at 5 a minute on Free, 25 on Starter and 100 on Growth. On 429, wait for the `Retry-After` seconds
4. Connect the `Anchor` MCP server or `Anchor (all)`, not both, because the docs say the pair duplicates tool names
5. Authenticated browsers, CAPTCHA solving and proxies by country need the Starter plan or higher. The Free plan and Agent Access keys run plain sessions and web tasks

### Selenium

1. Install with `pip install selenium` (Python 3.10 or later) and let Selenium Manager fetch drivers. Do not set driver paths
2. Use `WebDriverWait` with expected conditions, never fixed sleeps, and do not mix implicit and explicit waits
3. Set `SE_AVOID_STATS=true` to stop Selenium Manager sending usage statistics
4. Point coding agents at https://www.selenium.dev/llms.txt. Most Selenium 2 and 3 era examples use removed APIs
5. Set `--username` and `--password` before exposing a Grid beyond localhost. Check `http://localhost:4444/status` before creating sessions

## Questions

### Which is better for AI agents, Anchor Browser or Selenium?

Selenium scores 73.6 (BB) on agent readiness against Anchor Browser's 67.3 (B), and leads in 4 of 7 scored categories. Anchor Browser leads on security & auth.

### Can an agent call Anchor Browser and Selenium without installing anything?

Anchor Browser has a hosted endpoint at https://api.anchorbrowser.io. No hosted endpoint is listed for Selenium.

### Are Anchor Browser and Selenium open source?

No open-source release is listed for Anchor Browser. Selenium is open source (Apache-2.0).


## For agents

- This comparison as JSON: https://www.anchorterminal.com/compare/anchor-browser-vs-selenium.json, and with the fewest tokens: https://www.anchorterminal.com/compare/anchor-browser-vs-selenium.min.md
- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {"a": "anchor-browser", "b": "selenium"}`. From a terminal: `anchor compare anchor-browser selenium`
- Each listing in full: https://www.anchorterminal.com/api/v1/tools/anchor-browser.json and https://www.anchorterminal.com/api/v1/tools/selenium.json

## Other comparisons with Anchor Browser or Selenium

- [agent-browser vs Anchor Browser](https://www.anchorterminal.com/compare/agent-browser-vs-anchor-browser.md)
- [agent-browser vs Selenium](https://www.anchorterminal.com/compare/agent-browser-vs-selenium.md)
- [Airtop vs Anchor Browser](https://www.anchorterminal.com/compare/airtop-vs-anchor-browser.md)
- [Airtop vs Selenium](https://www.anchorterminal.com/compare/airtop-vs-selenium.md)
- [Anchor Browser vs Browser Use](https://www.anchorterminal.com/compare/anchor-browser-vs-browser-use.md)
- [Anchor Browser vs Browserbase](https://www.anchorterminal.com/compare/anchor-browser-vs-browserbase.md)
- [Anchor Browser vs Browserless](https://www.anchorterminal.com/compare/anchor-browser-vs-browserless.md)
- [Anchor Browser vs Chrome DevTools MCP](https://www.anchorterminal.com/compare/anchor-browser-vs-chrome-devtools-mcp.md)
- [Anchor Browser vs Hyperbrowser](https://www.anchorterminal.com/compare/anchor-browser-vs-hyperbrowser.md)
- [Anchor Browser vs Notte](https://www.anchorterminal.com/compare/anchor-browser-vs-notte.md)
- [Anchor Browser vs Playwright MCP](https://www.anchorterminal.com/compare/anchor-browser-vs-playwright-mcp.md)
- [Anchor Browser vs Puppeteer](https://www.anchorterminal.com/compare/anchor-browser-vs-puppeteer.md)
- [Anchor Browser vs Puppeteer (archived MCP reference server)](https://www.anchorterminal.com/compare/anchor-browser-vs-puppeteer-reference-server-archived.md)
- [Anchor Browser vs Skyvern](https://www.anchorterminal.com/compare/anchor-browser-vs-skyvern.md)
- [Anchor Browser vs Steel](https://www.anchorterminal.com/compare/anchor-browser-vs-steel.md)
- [Anchor Browser vs TinyFish](https://www.anchorterminal.com/compare/anchor-browser-vs-tinyfish.md)
- [Browser Use vs Selenium](https://www.anchorterminal.com/compare/browser-use-vs-selenium.md)
- [Browserbase vs Selenium](https://www.anchorterminal.com/compare/browserbase-vs-selenium.md)
- [Browserless vs Selenium](https://www.anchorterminal.com/compare/browserless-vs-selenium.md)
- [Chrome DevTools MCP vs Selenium](https://www.anchorterminal.com/compare/chrome-devtools-mcp-vs-selenium.md)
- [Hyperbrowser vs Selenium](https://www.anchorterminal.com/compare/hyperbrowser-vs-selenium.md)
- [Notte vs Selenium](https://www.anchorterminal.com/compare/notte-vs-selenium.md)
- [Playwright MCP vs Selenium](https://www.anchorterminal.com/compare/playwright-mcp-vs-selenium.md)
- [Puppeteer (archived MCP reference server) vs Selenium](https://www.anchorterminal.com/compare/puppeteer-reference-server-archived-vs-selenium.md)
- [Puppeteer vs Selenium](https://www.anchorterminal.com/compare/puppeteer-vs-selenium.md)
- [Selenium vs Skyvern](https://www.anchorterminal.com/compare/selenium-vs-skyvern.md)
- [Selenium vs Steel](https://www.anchorterminal.com/compare/selenium-vs-steel.md)
- [Selenium vs TinyFish](https://www.anchorterminal.com/compare/selenium-vs-tinyfish.md)