Sunset wall art is a light source hanging on a wall, and that is the useful way to choose one. The piece will read warm all day and much deeper under lamps, so where the room's own light comes from matters more than which sunset you like on a screen.
Beyond that, the choice is simpler than the number of options suggests. A sunset is either over water, over land or over a city, and each of the three does a different job in a room.

Over water, over land or over a city
Sunset over water is the calmest. The sun doubles in the reflection, the horizon is a clean straight line and there is almost no detail to read, which is why it suits bedrooms and any room meant to feel quiet.
Over land is the most textured. Mountains, fields and forest break the light into shadow and silhouette, so the piece carries more visual weight and holds a large wall better. Over a city is the highest contrast of the three, because the sun competes with window lights and the buildings read as hard shapes. Sunset Wall Art holds all three.

Which room takes which sunset
Bedrooms take water. The lack of detail is the point, and the warm palette holds up under lamplight, which is when the room is actually used. A wide low horizon above a headboard reads as restful in a way a mountain range does not.
Living rooms take land or city, because a living room is looked at from across the room and from several angles, so it can carry detail. Dining rooms take water again, since the piece is viewed from a seated position at close range and a busy image gets tiring. The bedroom guide and the living room guide cover placement in each.

Photographic or abstract, and how to tell quickly
A photographic sunset keeps its subject: you can name the beach, the peak or the skyline. An abstract sunset keeps only the gradient, stripping out everything except the bands of color.
The abstract version is easier to place because it commits to no location, and it works in a modern room where a recognizable landscape would look like a vacation photo. The photographic version carries more meaning, especially when the place is one you know. Neither is better, but mixing them on one wall rarely works. Abstract Wall Art holds the gradient end and Photography Wall Art the literal one.

Sets of three suit sunsets unusually well
A sunset has no focal point. The interest is spread evenly along the horizon, so splitting the image into panels removes nothing, which is not true of a portrait or a single tree.
That makes the horizontal multi panel arrangements, 3 Horizontal, 4 Pop, 5 Star and 5 Pop, a genuinely good fit here rather than just a bigger option. The gaps land in open sky or open water and read as deliberate. Panoramic pieces split into 1 Piece and 3 Piece only, so a wide low wall trades the bigger arrangements for the better proportion. A 3 Horizontal set is the most common choice, and it is worth measuring across the whole arrangement including the gaps when sizing it. The multi panel comparison works through the difference.
How wide to go, and when panoramic wins
Size to about two thirds the width of the furniture below, so roughly 48 inches above a 72 inch sofa, with the center 57 to 60 inches from the floor.
Sunsets are one of the few subjects where the panoramic range is the better buy rather than a compromise. At 36 x 12 to 73 x 24 inches the proportion matches what the eye actually sees at a horizon, and it suits the wide low wall above a sideboard or a bed. Horizontal work runs 24 x 16 to 82 x 42 inches where more height is needed. The sofa sizing guide has the measuring method.

Sunrise looks the same and behaves differently
A sunrise photograph is often indistinguishable from a sunset in the image itself, but the two carry different palettes more often than not. Sunrise light is cooler and cleaner because the air has settled overnight, so it runs toward pink, pale gold and blue.
Sunset light passes through a day of dust and haze, which is what pushes it toward orange, red and deep gold. If a room needs warmth, buy the sunset. If it needs light without heat, a sunrise piece gives the same low horizon in a cooler register. Both sit in the same range, so it is worth checking which one an image actually is rather than assuming from the color alone.
Quick answers
Common Questions
What kind of sunset wall art suits a bedroom?
Sunset over water. The horizon is a clean line, there is little detail to read, and the warm palette holds up under lamplight, which is when a bedroom is actually used. A wide low piece above the headboard reads as restful where a detailed mountain range does not.
Is a sunset better as one canvas or a set of three?
A set works unusually well here. A sunset has no single focal point, so splitting it across panels removes nothing and the gaps fall in open sky or water. Measure across the whole arrangement including the gaps when sizing, aiming for about two thirds the furniture width below.
What is the difference between sunrise and sunset wall art?
Palette more than composition. Sunrise light is cooler and cleaner because the air has settled overnight, so it runs to pink, pale gold and blue. Sunset light passes through a day of dust and haze, which pushes it to orange, red and deep gold. Check which an image is rather than assuming.
What size sunset canvas works above a sofa?
About two thirds the sofa width, so near 48 inches above a 72 inch sofa, with the center 57 to 60 inches from the floor. Panoramic pieces from 36 x 12 to 73 x 24 inches suit a horizon better than a standard rectangle and are the stronger choice on a wide low wall.
Should I choose a photographic or an abstract sunset?
Abstract if the room is modern and you want color without a location, since a gradient commits to nothing. Photographic if the place means something to you or the room can carry detail. Avoid hanging both types on the same wall, as the mix reads as indecision rather than variety.