Firefox 77.0.1 does not allow editing in code window but Chrome Version 83.0.4103.116 works OK Make a MATLAB Analysis to Send Email First get your ThingSpeak Alerts API key from the Account > My Profile The alerts API key will start with ‘TAK’. Create a new MATLAB analysis at Apps > MATLAB Analysis. Click the New button on the top. Choose the blank template and with this code. alert_body = 'This is the text that will be emailed'; alert_subject = 'This will be the subject of the email'; alert_api_key = 'YOUR_API_KEY_FROM_STEP_1'; alert_url= "https://api.thingspeak.com/alerts/send"; jsonmessage = sprintf(['{"subject": "%s", "body": "%s"}'], alert_subject,alert_body); options = weboptions("HeaderFields", {'Thingspeak-Alerts-API-Key', alert_api_key; 'Content-Type','application/json'}); result = webwrite(alert_url, jsonmessage, options); Adjust the alert body, subject and API key.