Browserless — Input & Output

Output Ports

Port	Operations	Description
success	All 8 operations	Browserless processed the request successfully. Output format varies by operation — see sections below.
error	All 8 operations	Invalid API token, page navigation failed, timeout exceeded (when BestAttempt=false), or selector not found. Includes `errorCode` and `message`.

screenshot — Success Output

Field	Type	Description
`data`	string (base64)	Base64-encoded PNG or JPEG image data. Decode and save to a file, or pass to an email/S3 upload node.
`contentType`	string	`image/png` or `image/jpeg` depending on the `Type` property.

{
  "data": "iVBORw0KGgoAAAANSUhEUgAAA...(base64 encoded PNG)...",
  "contentType": "image/png"
}

pdf — Success Output

Field	Type	Description
`data`	string (base64)	Base64-encoded PDF bytes. Decode and save as a `.pdf` file, or attach to an email.
`contentType`	string	Always `application/pdf`.

{
  "data": "JVBERi0xLjQKJeLjz9MKNiAwIG9iago...(base64 encoded PDF)...",
  "contentType": "application/pdf"
}

content — Success Output

Field	Type	Description
`data`	string	Full rendered HTML of the page after JavaScript execution. This is the `document.documentElement.outerHTML` value.
`contentType`	string	Always `text/html`.

scrape — Success Output

Returns a structured object for each selector rule provided in the Elements input property.

Field	Type	Description
`data`	array	Array of extraction result objects — one per selector in `Elements`.
`data[].selector`	string	The CSS selector that was matched.
`data[].results`	array	Array of extraction results from matched elements. Each item has `type` (text/attribute/html/eval) and `value` (the extracted value).
`data[].results[].attributes`	array	All HTML attributes of the matched element as key-value pairs.

{
  "data": [
    {
      "selector": ".product-title",
      "results": [
        { "type": "text", "value": "Widget Pro 3000" },
        { "attributes": [{ "name": "class", "value": "product-title h2" }] }
      ]
    },
    {
      "selector": ".product-price",
      "results": [
        { "type": "text", "value": "$29.99" },
        { "type": "attribute", "attribute": "data-price-cents", "value": "2999" }
      ]
    }
  ]
}

performance — Success Output

Returns the full Lighthouse audit JSON object. Key fields:

Field	Type	Description
`categories.performance.score`	number (0–1)	Overall performance score. Multiply by 100 for the familiar 0–100 score.
`categories.accessibility.score`	number (0–1)	Accessibility score.
`categories.seo.score`	number (0–1)	SEO score.
`audits.first-contentful-paint.numericValue`	number	First Contentful Paint in milliseconds.
`audits.largest-contentful-paint.numericValue`	number	Largest Contentful Paint in milliseconds.
`audits.cumulative-layout-shift.numericValue`	number	Cumulative Layout Shift score (lower is better).
`audits.interactive.numericValue`	number	Time to Interactive in milliseconds.

{
  "categories": {
    "performance": { "score": 0.87 },
    "accessibility": { "score": 0.94 },
    "seo": { "score": 1.0 }
  },
  "audits": {
    "first-contentful-paint": { "numericValue": 1240, "displayValue": "1.2 s" },
    "largest-contentful-paint": { "numericValue": 2350, "displayValue": "2.4 s" },
    "cumulative-layout-shift": { "numericValue": 0.02, "displayValue": "0.02" },
    "interactive": { "numericValue": 3100, "displayValue": "3.1 s" }
  }
}

download — Success Output

Returns data (base64-encoded binary content of the downloaded file) and contentType (the MIME type detected from the HTTP response headers).

unblock — Success Output

Returns data (full rendered HTML string of the unblocked page) and contentType (text/html). Also returns ttl (integer — seconds remaining in cache if TtlSeconds was set).

execute — Success Output

Returns data — the value returned by the JavaScript Code. Can be any JSON-serialisable type: string, number, boolean, array, or object. If the script throws an exception, the error port fires instead.

// If Code was: return document.title;
{ "data": "Acme Corp — Home" }

// If Code was: return { price: document.querySelector('.price').textContent, sku: document.querySelector('[data-sku]').dataset.sku };
{ "data": { "price": "$29.99", "sku": "WP-3000-BLK" } }

Error Port Output

Field	Type	Description
`status`	string	Always `"error"`.
`errorCode`	string	Error category: `navigation-failed`, `timeout`, `selector-not-found`, `invalid-token`, `script-error`.
`message`	string	Human-readable error description.

{
  "status": "error",
  "errorCode": "navigation-failed",
  "message": "net::ERR_NAME_NOT_RESOLVED at https://nonexistent.example.com"
}