REL is a native Mac browser built for AI agents, scripts, and scheduled tasks. Automate visible Chromium sessions with your tools, keep your logins, and take over whenever you need to.
CLI / Python / MCP / HTTP API / Rust
01 / Start building
Download REL and open it on your Mac. Choose your interface, run a first command, and see the browser at work.
# Save a rendered page to a file
rel https://example.com > example.html
# Navigate, wait, and capture the current page
rel navigate https://example.com
rel perform '[{"action":"wait-for","selector":"body"}]'
rel capture > page.htmlIn REL, choose Settings → General → Install Command Line. Then capture a page from your terminal.
CLI setup and guidefrom rel_playwright.sync_api import sync_playwright
with sync_playwright() as playwright:
browser = playwright.chromium.launch()
page = browser.new_page()
page.goto("https://example.com")
print(page.title())
browser.close()Install the REL Playwright adapter using the Python setup guide. Keep REL open while your script runs.
Python setup and guide{
"mcpServers": {
"rel": {
"command": "/Applications/REL.app/Contents/Resources/rel-mcp"
}
}
}Add REL to an MCP client that supports this JSON configuration, then restart the client. Install REL in Applications first.
MCP setup and client guides02 / The browser layer, handled
Real sessions, native browser actions, and control over every route. The same workspace for you, your scripts, and your agents.
Watch an agent work, step in when it needs you, and hand control back. Your browser sessions stay visible on your Mac.
Each session has its own cookies, storage, and browser identity. Keep saved logins and return to the work later.
Click, type, scroll, and navigate with native browser input. Agents use the same controls you see on the page.
Use a different proxy for each session, including authenticated proxies. Pause a session to cut its network access instantly.
Read rendered HTML or Markdown, inspect semantic structure, capture pixels, or combine structure and screenshots in one observation.
Reuse profiles with your proxy, browser identity, and filtering choices. Set exact viewports for repeatable captures and tests.
Block ads, trackers, or heavy images with per-session bandwidth controls. Keep more of your metered traffic for the content you need.
Choose a profile and model, write a prompt, and set a schedule. Give recurring research and browser tasks a place to run.
03 / Real work, recorded results
See how REL turns real websites into repeatable workflows, with source code, captured data, and a record of what was verified.
01 / Property research
A resumable Santa Cruz housing study using rel-crawlee and a persistent REL browser session. Property facts, Zestimates, and source captures, stored together in SQLite.
Read the case studySeptember 15, 2026 · Fresh crawl
Recorded September 15, 2026. Citywide coverage is unverified.
04 / Measured in a real browser
Recorded checks for session isolation, browser identity, and network behavior. Each result belongs to a specific tested build.
| Check | What was tested | Result |
|---|---|---|
| Session isolation | 100 alternating actions across 2 profiled sessions and 1 native session. | Passed |
| Canvas & WebGL | Distinct profile output with coherent graphics in page and worker contexts. | Passed |
| DNS & WebRTC | Distinct DNS routes. No WebRTC route leaks observed; proxy failure closes the route. | Passed |
| Audio identity | Distinct audio output per profile, within tolerance, with native-session behavior preserved. | Passed |
| Permissions | Allowed, denied, and unset permissions checked, including isolation between sessions. | Passed |
| Renderer restart | Session identity and WebRTC policy remain coherent after the renderer restarts. | Passed |
+1.88% median navigation time and +0.68 MiB per browser with browser identity enabled versus native behavior, using the same four-profile workload.
Tested in RELDebug on macOS with 50 navigation samples per stage. These are development-build results, not a certification of the current download. Chromium 152 validation is pending.
Download the recorded results05 / Start with one. Make room for more.
Start free with one focused workflow. Move to Pro when you need more sessions, profiles, and scheduled work.
Free
Everything you need for one focused browser workflow.
$3.99/ month
Remove the one-item limits when your work needs more room.
Already have a license key? Activate it in REL → Settings → Plan. Compare plans ↗