If you are like me, then probably your unread message count of gmail has got some nice 4 figure number (well mine was 8000+ this morning). Now obviously going through all the unread messages manually and checking them as read is something which is not humanly possible. Luckily there is a trick in gmail using which you can do it. I was feeling very irritated today morning and was checking the filters of gmail search. Finally I found a nice trick to do this with a single click. So, here I am sharing it with you. Just follow the 3 simple steps and you will be done in no time.
#1: Advance Search the Unread messages:
In the search bar shown above your messages, type is:unread and hit enter. This will show you all the messages which is labeled unread. But this will list only 20 messages (by default) per page. So, to mark them all as read, you need to do a little bit more.
#2: Select all the unread messages:
To select all the unread messages at once, scroll down a little. You will see something like Select all conversations that match this search. Hit the button and this should select all the messages (check the screenshot above).
#3: Mark all as read:
Hope you find this trick useful. If you know however anything better than this, do let us know through your comment.