Core feature · Developer API

A free Local API that powers AI agents and enterprise automation

Launch, close and query browser profiles over a local HTTP endpoint, and get back a debugging port you can attach to right away. Free, with no call limits — your fingerprint environments become just another component in your stack.

Automation shouldn't stall at the API layer

The old way

  • Automation APIs locked behind a higher-priced plan
  • Daily call quotas that kill batch jobs halfway through
  • No real docs — profiles have to be opened by hand

With NexBrowser

  • The Local API is free, with no cap on calls
  • One request spins up a profile and returns its debugging port
  • Selenium, Puppeteer and Playwright attach as-is

Everything developers actually ask for

From launching a profile to plugging in an AI agent — all of it driven by code.

Free, with unlimited calls

The API ships with the client at no extra cost and no request cap — the free plan runs full automation too.

Works with the frameworks you use

It hands back a standard debugging port, so Selenium, Puppeteer, Playwright and WebDriver run your existing scripts unchanged.

Manage profile lifecycles in code

Start, stop and check status through the API, so batch jobs can spin profiles up and tear them down on demand.

Wire in AI agents and internal systems

Connect frameworks like browser-use and Playwright MCP, or embed the API in your own back office and CI pipelines.

Three steps to put a browser profile inside your code

The typical call flow is just three steps: launch the profile, take the debugging port it returns, then attach with the framework you already know. Fingerprints, proxies and cookie isolation are handled at the profile level, so your scripts only deal with business logic.

01

Step one: call the local endpoint to launch a specific profile, with its fingerprint and proxy settings loaded automatically.

02

Step two: the response gives you that profile's debugging port — nobody has to open a window in the client.

03

Step three: connect Selenium, Puppeteer or Playwright to the port and run your existing scripts as usual.

Frequently Asked Questions

Is the Local API free? Are there call limits?

It is completely free and there is no cap on the number of calls. The API ships with the Windows client and is available on the free plan as well. You never have to buy a separate tier just to automate.

Which automation frameworks are supported?

The API returns a standard debugging port, so Selenium, Puppeteer, Playwright and WebDriver can all take over a profile directly. Existing scripts usually need no rewriting — just point the connection at the port you get back.

Can I connect an AI agent?

Yes. Agent frameworks such as browser-use and Playwright MCP can attach to a NexBrowser profile through its debugging port, so the agent operates inside a real environment with its own fingerprint and proxy. That makes it practical to hand multi-account workflows to AI.

What if I don't want to write code?

Use the built-in no-code RPA instead. It offers a drag-and-drop flow builder, recorded steps, scheduling, retries and variables, and runs the same flow across many profiles at once. Teammates who don't code can set up their own tasks.

Ready to manage every account profile in one place?

Install in 3 minutes. 10 free windows on sign-up, no credit card.

Free Download for Windows

Already have an account? Sign in to the client to sync all profiles.