<img>

<iframe width="450" height="260" style="border: 1px solid #cccccc;" src="https://thingspeak.com/apps/plugins/586278"></iframe>

<iframe width="450" height="260" style="border: 1px solid #cccccc;" src="https://thingspeak.com/channels/2682049/charts/1?bgcolor=%23ffffff&color=%23d62020&dynamic=true&results=60&title=%3Cimg%3E&type=line"></iframe>