from what I known is, when you type "info:domain.com" on the google, then there will be no result. it means your site already got deindexed from there.
there is no any specific tool for checking penalty. but yes you can feel your keyword drastically down and decreasing traffic.
hello Step 1: Login to Google Webmaster tools there are 2 types of penalties and it is important to know their difference. Manual Penalty: A human (probably from the webspam team), imposed a penalty to your website. This can happen because of a number of reasons and it can be either site-wide, affecting the website as a whole or partial i.e. affecting only some pages of your site. In this case, Google will give you an indication of what the problem is together with a list of actions you can take to correct the issues. Once you make the necessary changes, you can submit a reconsideration request and they will tell you if the penalty has been removed or not. Algorithmic Penalty: This is the most common type and it is automatic. Algorithmic penalties are not reported to webmaster tools and there is no option to fill in a reconsideration request. They only way to identify if you were hit by an automatic penalty Algorithmic penalties are a result of the continuous changes Google is making to their ranking algorithms the steps below to find out if you were impacted by an algorithmic penalty. Step 2: Login to Google Analytics and review your Google traffic The best way to check if your website was penalized by an automatic penalty is to login to Google analytics and review your Google organic traffic. If you see a drop in traffic during the dates that Google released an algorithmic change then most probably you were hit and that’s the reason that your traffic dropped. Manual Penalty can be improved and can get back your site again but if you get algorithm penalty its not possible to get back again. You must follow the rules what google provides. always try to remember.. If GOOGLE happy your site is always ok. thats why always follow SEO rules and implement them n your site in a right way. thank u