How to Check a Texture Tiles Without Seams

The texture looks seamless in the editor. You apply it to a wall in the scene and there’s an obvious grid across the whole surface — but when you zoom in on the tile edge, nothing’s wrong.

That’s because there are two different faults and they look similar in a small preview. One is fixable in an afternoon; the other needs a different texture.

Seams versus repetition

A seam is a visible discontinuity where one tile meets the next. Colour doesn’t match, a shadow stops abruptly, texture direction changes. It shows as a hard line along the tile boundary and it’s a property of the edges.

Seams are fixable. The standard workflow is to offset the image by half its width and height, which moves the edges into the middle where you can see and heal them, then offset back.

Repetition is when a distinctive feature in the texture — a bright pebble, a crack, a knot in wood — recurs on a regular grid. There’s no discontinuity anywhere; the tiling is technically perfect. The eye simply recognises the feature and locks onto the pattern.

Repetition is not fixable at the edges, because the edges aren’t the problem. The solutions are a larger source texture, removing the distinctive feature, or breaking the pattern at render time with variation, detail maps, or randomised rotation per tile.

Why the small preview lies

At 2×2 tiles, repetition is invisible — a feature appearing four times isn’t a pattern yet. At 8×8 it’s obvious, because sixty-four instances on a regular grid is exactly what the visual system is built to notice.

Seams behave the opposite way: they’re clearest up close and can disappear at a distance.

So checking at one tile count finds one fault. Check at the count the surface will actually use, and check at both close and far viewing distances.

The lighting problem

A third fault worth knowing about: a texture photographed with directional light has shadows baked into it. Tile it and every tile has a shadow falling the same way, which reads as a repeating pattern of light and dark regardless of how well the edges match.

Flattening the lighting before tiling is often more important than fixing the seams.

Common mistakes to avoid

• Checking at 2×2 and concluding the texture is fine.
• Trying to fix repetition by working on the edges.
• Using a photo with visible directional shadows as a tileable source.
• Testing at editor zoom rather than at the distance the surface will be viewed from.
• Making a texture seamless by heavy blurring at the edges, which produces a soft band that’s its own artefact.

How to do it with Seamless Texture Checker

The Seamless Texture Checker tiles the texture in your browser, with the file staying on your device.

1. Upload the texture and view it tiled at 4×4 first.
2. Look for two distinct faults — hard lines at the boundaries, and features recurring on a grid.
3. Zoom out to 8×8, where repetition becomes visible.
4. Fix seams by offsetting and healing; fix repetition with a larger source or render-time variation.

Other browser-only image tools are in the tools directory.

Frequently asked questions

What’s the difference between a seam and repetition?

A seam is a visible discontinuity at the tile edge, fixable by offsetting and healing. Repetition is a distinctive feature recurring on a grid, and no edge fix removes it.

Why does my texture look fine at 2×2 and bad at 8×8?

Because repetition only becomes visible once the pattern recurs enough times for the eye to lock onto it. Always check at the tile count the surface will use.

How do I fix a seam?

Offset the image by half its width and height so the seams move to the centre, then heal them with surrounding texture. That fixes edges but not repetition.

Final thought

Check at high tile counts and from a distance. Every texture is seamless at 2×2, and none of them are used at 2×2.

Try the free Seamless Texture Checker