1K, 2K or 4K? Choosing texture resolution
Texture resolution is the most common place to waste memory without gaining anything visible. The number that matters is not the size of the image — it is how many of its pixels land on a given patch of the model, and how close the camera ever gets.
The short answer
1K means 1024×1024 pixels, 2K is 2048×2048, 4K is 4096×4096. Each step doubles the edge length and quadruples memory. Choose by texel density — texels per unit of surface — not by habit: a 4K map on a distant background prop looks identical to a 1K one and costs sixteen times the memory.
What the numbers mean
The “K” is roughly a thousand pixels along one edge, rounded from the actual powers of two: 1024, 2048, 4096. Powers of two remain the convention because GPUs generate mipmaps and compress blocks most efficiently at those sizes.
Memory scales with area, not edge length. Going from 1K to 2K is four times the data; 1K to 4K is sixteen. A full PBR set multiplies that again — base colour, normal, roughness, metallic, and height are five maps, so one 4K material can cost more memory than an entire set of 1K ones.
Texel density is the real measure
Texel density describes how many texture pixels cover a given amount of surface — often quoted as pixels per centimetre or per metre. It is what actually determines whether a surface reads as sharp or soft.
This is why resolution is a property of the pairing, not the image. A 2K map on a coin is enormously dense; the same 2K map stretched across a building facade is mush. Consistent texel density across a scene matters more than any single asset's resolution, because mismatches are what the eye notices.
Choosing a size in practice
Start from how close the camera gets. Hero assets the player inspects up close justify 4K. Mid-ground props are almost always fine at 2K. Background geometry, and anything using a tiling material repeated across a large surface, rarely needs more than 1K.
Tiling changes the arithmetic entirely. A 1K texture repeated eight times across a wall delivers the same perceived detail as an 8K unique map, at a sixty-fourth of the cost. Reach for tiling and detail overlays before reaching for a bigger image.
When more resolution stops helping
If the source detail is not there, upscaling the map adds bytes and nothing else. A photo scanned at 2K exported to 4K is a 4K file containing 2K of information.
Different channels also tolerate different sizes. Roughness, metallic, and ambient occlusion are usually low-frequency and survive being stored at half the base colour's resolution. Normal maps are the ones to keep sharp — they carry the surface detail the eye reads as geometry.
Frequently asked questions
What resolution should my textures be?
Match texel density to camera distance: 4K for hero assets seen up close, 2K for mid-ground props, 1K for background geometry and tiling materials. Consistency across the scene matters more than any single number.
How much bigger is a 4K texture than a 1K one?
Sixteen times, in memory. Each step from 1K to 2K to 4K doubles the edge length and therefore quadruples the pixel count.
Do textures still have to be powers of two?
Modern GPUs accept non-power-of-two textures, but powers of two still compress and mipmap most efficiently, so 1024, 2048, and 4096 remain the practical default.
Can every map in a PBR set be a different size?
Yes, and it is good practice. Keep the normal map sharp, and store low-frequency channels like roughness, metallic, and AO at half resolution to save memory with no visible cost.
Export organised PBR map sets at the resolution your scene actually needs — up to 4K, straight from the browser.