> ## Documentation Index
> Fetch the complete documentation index at: https://docs.brightdata.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Scraper Studio worker types

> Choose between Browser worker and Code worker in Bright Data Scraper Studio based on whether your target site needs UI interaction or plain HTTP requests.

Bright Data Scraper Studio runs every scraper on one of two worker types: Browser worker (a real headless browser) or Code worker (raw HTTP requests). Pick the one that matches the minimum level of interaction your target site needs, Code worker is faster and cheaper, so start there and switch only if Code worker cannot reach the data.

## Browser worker vs Code worker

|                             | Browser worker                                                     | Code worker                                          |
| --------------------------- | ------------------------------------------------------------------ | ---------------------------------------------------- |
| Execution model             | Headless browser session                                           | Direct HTTP requests (like `curl` or `requests.get`) |
| Runs JavaScript             | Yes                                                                | No                                                   |
| Clicks, scrolls, form input | Yes                                                                | No                                                   |
| Best for                    | Dynamic pages, SPAs, login flows, infinite scroll, GraphQL capture | Static HTML, sitemap crawls, public JSON APIs        |
| Speed                       | Slower (browser startup, full page load)                           | Faster (single HTTP round trip)                      |
| Cost per page load          | Higher                                                             | Lower                                                |

## When should I use Browser worker?

Use Browser worker when any of the following is true:

* The target data is rendered client-side by JavaScript and is not present in the raw HTML response
* You need to click, scroll, hover, or type to reach or reveal the data
* You need to solve a cookie banner or dismiss a popup before the content renders
* You need to capture network traffic with `tag_response`, `tag_script`, or `capture_graphql`
* You need to log in, hold a session, or interact with a form

## When should I use Code worker?

Use Code worker when all of the following are true:

* The full target data is present in the raw HTML response or in a public JSON endpoint
* No JavaScript execution is required to render the data
* No click, scroll, or type interaction is required
* You are crawling sitemaps, RSS feeds, or API endpoints

<Tip>
  Start with Code worker. If the data you need is not in the raw response, switch to Browser worker. You can change worker type on the same scraper at any time.
</Tip>

## Which functions are Browser worker only?

Bright Data Scraper Studio functions that depend on a live browser session throw an error when called from a Code worker. Choose Browser worker if your scraper needs any of these:

| Category                 | Functions                                                                                                                                                        |
| ------------------------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Waiting on the DOM       | `wait`, `wait_any`, `wait_for_text`, `wait_hidden`, `wait_visible`, `wait_network_idle`, `wait_page_idle`                                                        |
| Scrolling                | `scroll_to`, `scroll_to_all`, `load_more`                                                                                                                        |
| Traffic tagging          | `tag_response`, `tag_all_responses`, `tag_script`, `tag_image`, `tag_video`, `tag_screenshot`, `tag_download`, `tag_window_field`, `tag_serp`, `capture_graphql` |
| Keyboard and mouse input | `click`, `right_click`, `hover`, `mouse_to`, `press_key`, `type`                                                                                                 |
| Browser configuration    | `browser_size`, `emulate_device`, `freeze_page`                                                                                                                  |
| Anti-bot                 | `solve_captcha`, `close_popup`                                                                                                                                   |

## Frequently asked questions

<AccordionGroup>
  <Accordion title="Can I switch worker type after building the scraper?">
    Yes. Open the scraper in the Bright Data Scraper Studio IDE and change the worker type in the **Settings** panel. If you switch from Browser worker to Code worker, remove any calls to the browser-only functions listed above or the scraper will throw an error on the next run.
  </Accordion>

  <Accordion title="Is Code worker really faster than Browser worker?">
    Yes. Code worker issues a single HTTP request with no browser boot and no page render, so the round trip completes in a fraction of the time a browser-worker run takes. The exact speedup depends on the target site, but Code worker jobs typically finish in seconds.
  </Accordion>

  <Accordion title="Does Browser worker support capturing background API calls?">
    Yes. Use `tag_response` or `tag_all_responses` to capture any XHR or fetch the page makes, and `capture_graphql` to capture and replay GraphQL queries. See [Scraper Studio functions](/datasets/scraper-studio/functions) for the full reference.
  </Accordion>
</AccordionGroup>

## Related

<CardGroup cols={2}>
  <Card title="Scraper Studio functions" icon="code" href="/datasets/scraper-studio/functions">
    Full reference for interaction and parser commands
  </Card>

  <Card title="Best practices" icon="list-check" href="/datasets/scraper-studio/best-practices">
    Recommended patterns for writing efficient scrapers
  </Card>
</CardGroup>