Paintings are matched by shape, not by size you pick
Most custom painting packs fail because the artwork's aspect ratio does not match any slot. Here is how matching actually works.
Minecraft 26.3 ships 51 paintings, and they are not interchangeable canvases. Each one has a fixed block footprint, and the game only ever places a painting whose footprint fits the wall space it found — and of those, only the largest. A painting is chosen by its declared width and height, never by its image, so declare the wrong size and your artwork is never picked for the walls you had in mind.
The slot shapes that exist
The 51 paintings break down by width-by-height in blocks:
| Size | Count |
|---|---|
| 1x1 | 8 |
| 2x2 | 12 |
| 3x3 | 9 |
| 4x4 | 5 |
| 4x2 | 5 |
| 2x1 | 5 |
| 1x2 | 3 |
| 3x4 | 2 |
| 4x3 | 2 |
Note the asymmetry: 4x2 exists but 2x4 does not, and 1x2 exists but 2x1 also exists separately. Orientation is not mirrored for you.
Why your image gets rejected
A painting's texture is not stretched to fit whatever wall it lands on. The game picks a painting whose declared size fits the available space, then spreads that painting's whole texture over that size. So a source image must match the slot's aspect ratio — an image of the wrong shape is squashed, not cropped.
Vanilla draws 16 pixels per block: a 1x1 painting is 16x16 and a 4x4 is 64x64. Any resolution at the right ratio works; the size in blocks is registry data (width, height), and the texture is stretched onto it.
If you make a wide panoramic painting and only 1x1 space is free on the wall, a 1x1 painting appears instead of yours. The pack is fine; the placement is not. And a custom painting is only ever picked at random if it is in the #minecraft:placeable tag.
Java and Bedrock diverge here
Java resource packs address paintings through the vanilla painting registry and a texture atlas. Bedrock uses its own pack manifest structure and a different folder layout. The artwork files themselves are the same PNG dimensions, but a pack built for one edition will not load in the other. Build and download separately.
The Bedrock side also handles pack versioning more strictly, so a pack that works today can be flagged after a game update even though no painting changed.
Practical matching
Work backwards from the wall, not forwards from the image:
- Measure the wall in blocks. A 3-wide, 2-tall gap fits no 3x2 painting — none exists in the list above — so the game hangs the largest one that does fit, a 2x2, and leaves a column bare.
- Match your source image's aspect ratio to a slot that actually exists before you resize anything.
- Keep one pack per edition. Mixing Java and Bedrock assets produces a pack that loads in neither.
The tool matches your uploaded image to the slot whose shape fits it and hands back the finished pack for Custom Paintings.