Cotton paper, no frame. Frame it yourself or clip it to the wall.
Four things decide it: how much of the frame the face occupies, whether it is sharp, whether the eyes are readable, and whether there is enough light to have recorded fur detail. Megapixels come fifth, and a long way behind.
The usual advice — "use a high-resolution image" — is close to useless, because a 48-megapixel photo of a dog standing across the garden puts perhaps 300 pixels on the head. A 12-megapixel photo taken from two meters away, with the head filling a third of the frame, puts something like 1,500. The second one prints beautifully at 60 cm; the first one does not print well at any size.
A practical test: open the photo on your phone and pinch to zoom until the head fills the screen. If it still looks solid at that magnification, it will hold at print size. If it turns into mush, no software recovers it.
In a portrait, the viewer looks at the eyes first and decides in a fraction of a second whether the animal is "there". So the eyes are the test:
Dark-coated animals are where this fails most often, because phones expose for the room and let the face fall into shadow. Black dogs and black cats are worth reshooting near a window rather than trying to rescue.
There are two kinds of soft photo, and they are not equally bad. Out-of-focus — the phone focused on the sofa — is usually fatal for fine detail like whiskers. Motion blur — the head moved during a slow exposure — is always fatal, because the information is smeared rather than merely softened.
Zoom to 100% on the whiskers and the eyelashes. If they are individual lines, you are fine. If they are a haze, the printed piece will look wrong from a meter away even if the phone screen looked acceptable.
Portraits are usually taller than they are wide, and that is the shape most rooms want on a wall. A photo where the animal sits in the middle of a wide landscape frame still works, because the crop is rebuilt around the head and chest — but you need room to crop into. A face already jammed into the corner of the frame, half cut off, cannot be extended.
The rule of thumb: leave the whole head and some of the chest inside the frame, with a little space above the ears. Everything else is negotiable.
Under dim light a phone raises ISO, which produces grain, and then applies noise reduction, which smears the grain into blotches. On a screen this is invisible. Printed at 50 cm on canvas, it shows up as a slightly plastic look across the fur.
This is the main reason a daylight photo taken beside a window outperforms an evening photo taken under lamps, even when both look fine on a phone. If you have five minutes, the phone photo guide covers how to set that up.
All of the above is a way of guessing. The direct method is to upload the photo and look at the result, which costs nothing: the portrait appears on screen, and you decide from there whether it is worth printing. If it does not hold up, try a different source photo — the difference between two photos of the same animal is usually much larger than any setting.
Cotton paper, no frame. Frame it yourself or clip it to the wall.
Stretched over a wooden bar. Hangs as it comes, no glass in the way.
Wooden frame and mat board. Arrives ready to hang, hanger fitted.
Canvas in a floater frame. The heaviest of the four, and the one that reads as a piece.
Fewer than people assume. A 12-megapixel phone photo where the head fills a third of the frame carries more usable detail than a 48-megapixel photo taken from across a room. What matters is pixels on the face, not pixels in the file.
Often yes, if the face is sharp and reasonably large in the frame. Social platforms recompress images, so look closely at the eyes and whiskers before deciding — that is where the damage shows first.
Yes, and for older pets it is sometimes the only option. Lay the print flat in daylight, shoot straight down without flash, and get close enough that the face fills most of the frame.
No. Motion blur destroys information that nothing can put back. A sharp photo in bad light is far more usable than a soft photo in good light.