How many different endings are there in Fallout 4?

According to the wiki, there are 4:

• Brotherhood Ending

Supported by the rebuilt Liberty Prime, the Brotherhood assaults the Institute and blows up its reactor. For the player character's service, Elder Maxson promotes the Sole Survivor to the highest rank of Sentinel.

• Minutemen Ending

The Institute is infiltrated and destroyed, sparing the Commonwealth of their oppression.

• Railroad Ending

With the help of Deacon, Tinker Tom, and a stolen vertibird, the Sole Survivor infiltrate the Prydwen and destroy it from the inside, causing it to crash. Later, the Institute is infiltrated and destroyed. The two organizations most opposed to Synth freedom are eliminated and the Railroad can continue its work in relative peace.

• Institute Ending

The Institute and the Sole Survivor attack and eliminate the Railroad. Later on, with the help of Institute synths, Liberty Prime is hacked and shoots the Prydwen out of the sky. After returning to the Institute, the Sole Survivor has a heart-to-heart with Father and assume his position after he dies.

You have 4 endings. Sadly, nothing you do aside from that will effect the end. It is not like New Vegas where you her to see the outcome of companions and side quests, it's actually rather bland.

Actually guys, there are 5 endings. Brotherhood, Institute, Railroad and 2 Minute Men endings. The Minute Men ending has you destroy the Institute and Brotherhood but there is sort of a hidden ending where you kill off the Institute, but the other 3 factions can "live in peace" lmao.

The benefit of this outcome is you can get the side quests of the 3 surviving factions. Just don't talk to P.A.M. in the Railroad.

The only companion you lose doing this ending is X6-88 assuming you don't kill Danse. Speaking of which keep Danse away from the Brotherhood and the Railroad if you keep him alive. Trust me on this.