Arefly

Check if the Email’s Gravatar is exist.
檢測指定郵箱的Gravatar是否存在
Example:
<pre><code>if(validate_gravatar("name@domain.com")){
 echo "This Email have Gravatar!";
}else{
 echo "This Email do not have Gravatar!";
}
</code></pre>

Validate Gravatar

Check if the Email's Gravatar is exist. 檢測指定郵箱的Gravatar是否存在

Piotr Po

WCAG Validator check all posts with the WCAG standard
You can validate all post in Tools > WCAG Validator. When you update the post validator generate also a new report.

Validate Gravatar vs WCAG Validator