The B&W topic is bringing in many titles that deserve to be there, with no attempt to go for The Best of the batch.
I know it’s a ridiculous quest but what (in your estimation) is the Best Ever Western Movie?
I’ll name my choice later so as not to poison the well. 
“The Searchers”.
The Good The Bad and The Ugly
Butch and Sundance
The Searchers is a great movie. An all-time Western classic. No doubt about that.
I wish you would have been more specific because there are so many diff kinds of Westerns with diff themes. Many love stories. Many action adventures. Many who dunnits as well.
I’ll recommend one of my favorites to you. Better yet, how about letting me recommend a site that I found after Googling “best western movies ranked”?
The following site lists 100 Western movies and ranks them in order:
This site should keep you busy for a very long time. If I could pick only one of these, it would be “The Treasure of The Sierra Madre (1948)”. It is one of the finest films ever made.
The Searchers is Number 14 and The Treasure of Sierra Madre is Number 39.
There are a great many fabulous films on this list. I hope you will enjoy.
It’s not normally high on everyone’s list, but Big Jake is one of my favorites. I’d also add:
Unforgiven
Fistful of Dollars
3:10 to Yuma
That IMDB list is clearly fucked up: it puts My Darling Clementine (my favorite classic Western movie) at #90 FFS.
I have to go with Shane (1953) because it was the first “grown up” Western I ever saw when it was just out. I later saw many of the earlier ones that would probably outrank it on the list above. And it spawned many others that were technically and artistically “better” including several of Eastwood’s creations. But for my just-out-of-grade-school appreciation set, it was The Boss for many years. And it still holds up under scrutiny. Jack Palance will never be topped as a baddie.
High Noon, Unforgiven, Pale Rider.
ETA - you asked for the best, so I’m going with High Noon.
Support Your Local Sheriff
Stagecoach
Once Upon a Time in the West.
My top 7 (in chronological order):
The Wind (Sjostrom, 1928)
The Man from Laramie (Mann, 1955)
Rio Bravo (Hawk, 1959)
The Good, the Bad and the Ugly (Leone, 1966)
The Wild Bunch (Peckinpah, 1969)
McCabe & Mrs. Miller (Altman, 1971)
Dead Man (Jarmusch, 1995)
Best: Red River
Favorite: She Wore A Yellow Ribbon
Oh here we go again. How many threads is this gonna spawn?
Difficult to name one. And there are some great ones listed above. But, the choice is obvious.
It has to be Blazing Saddles.
I have to agree. IMDB lists often have some wacky elements. I think it’s because they are formed by people voting and I don’t know just how easy or difficult it is for people to “control” parts of the voting process.
I’ve seen My Darling Clementine. But it was so long ago that I don’t remember anything about it.
It sure does have a stellar cast though. I don’t think I’ve ever seen such an all-star cast in a Western:
Henry Fonda, Victor Mature, Walter Brennan, Linda Darnell, Tim Holt, Ward Bond and John Ireland are all major actors in Hollywood Westerns.
I will def have to watch it again and I thank you for the recommendation.
The Man Who Shot Liberty Valance.
Winchester 73
Hang Em High
A tie between The Magnificent Seven, and The Good, The Bad and The Ugly.
The Good The Bad The Ugly
Tombstone
Unforgiven
Back to the Future 3.