The average browser page load time (or response time) appears at the top right of the main chart of your Summary page. This value is labeled Browser and shows the average page load time in seconds.
Average page load time
To obtain the average for the time range (default is last 30 minutes), use the following command. Be sure to replace the ${APP_ID} and ${API_KEY} variables in this example with your specific application ID and REST API key.
curl -X GET "https://api.newrelic.com/v2/applications/${APP_ID}/metrics/data.json" \
-H "X-Api-Key:${API_KEY}" -i \
-d 'names[]=EndUser&values[]=average_response_time&summarize=true'