Execute Browser Code

Execute code in a sandboxed browser environment.

POST /browser/{sessionId}/execute

Execute code in a browser session

cURL

curl --request POST \
  --url https://api.firecrawl.dev/v2/browser/{sessionId}/execute \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "code": "<string>",
  "language": "node",
  "timeout": 150
}
'

200

{
  "success": true,
  "stdout": "<string>",
  "result": "<string>",
  "stderr": "<string>",
  "exitCode": 123,
  "killed": true,
  "error": "<string>"
}

Headers

Header	Value
Authorization	Bearer <API_KEY>
Content-Type	application/json

Request Body

Parameter	Type	Required	Default	Description
code	string	Yes	-	Code to execute (1-100,000 characters)
language	string	No	"node"	Language of the code: "python", "node", or "bash" (for agent-browser CLI commands)
timeout	number	No	-	Execution timeout in seconds (1-300)

Response

Field	Type	Description
success	boolean	Whether the code executed successfully
stdout	string	Standard output from the code execution
result	string	Standard output from the code execution
stderr	string	Standard error output from the code execution
exitCode	number	Exit code of the executed process
killed	boolean	Whether the process was killed due to timeout
error	string	Error message if execution failed (only present on failure)

Example Request

curl -X POST "https://api.firecrawl.dev/v2/browser/550e8400-e29b-41d4-a716-446655440000/execute" \
  -H "Authorization: Bearer $FIRECRAWL_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "code": "await page.goto(\"https://example.com\")\ntitle = await page.title()\nprint(title)",
    "language": "python"
  }'

Example Response (Success)

{
  "success": true,
  "result": "Example Domain"
}

Example Response (Error)

{
  "success": true,
  "error": "TimeoutError: page.goto: Timeout 30000ms exceeded."
}

Are you an AI agent that needs a Firecrawl API key? See firecrawl.dev/agent-onboarding/SKILL.md for automated onboarding instructions.

Authorizations

Authorization · string · header · required

Bearer authentication header of the form Bearer <token>, where <token> is your auth token.

Path Parameters

sessionId · string · required

The browser session ID

Body

application/json

code · string · required

Code to execute in the browser sandbox

Required string length: 1 - 100000

language · enum<string> · default: node

Language of the code to execute. Use node for JavaScript or bash for agent-browser CLI commands.

Available options: python, node, bash

timeout · integer

Execution timeout in seconds

Required range: 1 <= x <= 300

Response

200

application/json

Code executed successfully

success · boolean

stdout · string | null

Standard output from the code execution

result · string | null

Standard output (alias for stdout)

stderr · string | null

Standard error output from the code execution

exitCode · integer | null

Exit code of the executed process

killed · boolean

Whether the process was killed due to timeout

error · string | null

Error message if the code raised an exception