Seamless Pattern Checker & Repeat MakerNew
Drop a repeat tile to see it in full-drop, half-drop and half-brick, with every visible seam painted red. Offset or blend the seams away, then export the tile, the half-drop repeat tile or a preview.
Private — your pattern never leaves your browser.
Drop a pattern tile anywhere on the page, or try it with a sample tile that isn’t seamless yet.
How to check if a pattern is seamless
Short answer: repeat the tile and look at the joins. A seamless tile’s right edge flows into its left edge and its bottom into its top, so no line appears where copies meet. Drop your tile above: the checker compares every pixel along each join with the detail right next to it and gives each join a verdict — and the heatmap paints any visible seam red.
Your eye is good at spotting a grid once it knows where to look, but at a normal zoom level a 2 px mismatch can slip through — and then shows up as a stripe every 10 inches on a finished blanket. This checker does the looking for you. A join counts as seamless when the difference across it is no bigger than the ordinary pixel-to-pixel difference in the artwork next to it, so busy textures and flat colours are judged fairly. Everything runs in your browser; the tile is never uploaded, which matters when the pattern is your product.
Repeat types, in Spoonflower’s words
| Repeat | What it does | Good for |
|---|---|---|
| Basic (full drop, block) | Tiles straight up and down in a grid. | Geometrics, checks, stripes, any tile made in a grid. |
| Half-drop | Each column moves down by half a tile — “a half-step vertically as you move to the right”. | Florals and scattered motifs: it hides the grid. |
| Half-brick | Each row moves sideways by half a tile — “like bricks”. | Horizontal motifs, borders that shouldn’t line up. |
| Center | One copy of the image in the middle of the fabric — no repeat. | Panels and placement prints. |
| Mirror | Flips the design into four mirrored quarters. | Kaleidoscope and damask looks from a simple motif. |
This tool previews and checks the three that tile a single design — basic, half-drop and half-brick. A tile is made for one repeat: a tile that is perfect in basic will usually show seams in half-drop, so check it in the repeat you will order.
How to fix a pattern that isn’t seamless
- Offset by half. The tile is moved by half its width and height (for half-drop by half the width and a quarter of the height; for half-brick the other way round), so its edges meet in the middle. The outer edges now tile perfectly, and the join in the middle is marked in red.
- Paint over the red cross in your design app — move a motif across it, clone some background, or add a new element on top. Keep clear of the outer edges.
- Check again. Drop the fixed tile back in; every pill should turn green.
Blend edges does it automatically: it mixes the tile with its offset copy so the joins fade out, tight at the edges or soft over the whole tile. It works beautifully on watercolour washes, paper, linen and noise textures, and it can leave faint ghosts on crisp illustrations — for those, use Offset and fix the cross by hand.
Export for print shops
- Tile (PNG) — the tile as it is now, for Spoonflower (choose the same repeat there) or your own design app.
- Half-drop repeat tile — a half-drop repeats exactly as a basic repeat of a tile twice as wide: the tile on the left and the same tile dropped by half on the right. Upload it as a basic repeat to shops or apps that only have a grid. For half-brick the tile is twice as tall.
- Pattern preview (JPG) — a 2400 × 1600 px image of the repeat at the current scale, for listings and to show clients.
Scale and resolution: Spoonflower prints at a default of 150 DPI, so the tile’s pixels ÷ 150 is how often it repeats in inches — a 1500 px tile repeats every 10 in. Its help centre notes that a file prepared at 300 pixels per inch first shows at double size, and you scale it on the design page. The tool shows the repeat size at 150 and 300 DPI under the preview.
Common mistakes
- Cropping a finished pattern to make a tile. A random crop is almost never seamless — offset it and fix the cross.
- Anti-aliased or soft edges. Exporting with a transparent or blurred border leaves a faint line. Export the tile edge to edge.
- An odd number of pixels in a half-drop. Half of 1001 px isn’t a whole pixel, so the drop can’t be exact. Keep tile sizes even.
- Motifs lined up in a grid. Even a seamless tile looks like wallpaper squares if the big motifs sit in rows. Try half-drop.
- Too few pixels. A 600 px tile at 150 DPI only repeats every 4 in; enlarging it later blurs it. Upscale with the AI Image Upscaler before you check it.
FAQ
How do I know if my pattern is seamless?
Repeat it: when the tile is placed next to copies of itself, the right edge must continue into the left edge and the bottom into the top, with no visible line. This checker compares every pixel pair along those joins against the detail next to them and paints the joins that stand out red.
What is a half-drop repeat?
Each column of tiles is shifted down by half a tile compared with the column before it. Spoonflower describes it as the design repeated with a half-step vertically as you move to the right. It hides the grid and is popular for florals and scattered motifs.
What is the difference between half-drop and half-brick?
Half-drop shifts every other column by half the tile height; half-brick shifts every other row by half the tile width, like bricks in a wall. A tile has to be made for the repeat you pick: a tile that is seamless in a basic repeat will usually show seams in half-drop.
How do I make a tile seamless?
Offset it by half its width and height so the edges meet in the middle, paint over the cross where they meet, and it tiles cleanly. The Offset button does the first step and marks where to fix; Blend edges hides seams automatically on textures like watercolour, paper or noise.
My print shop only has a basic repeat — can I still sell a half-drop?
Yes. A half-drop repeats exactly as a basic repeat of a tile twice as wide: the tile on the left and the same tile moved down by half on the right. Download the half-drop repeat tile and upload it as a basic repeat. For half-brick it is twice as tall.
What resolution should a repeat tile be?
Spoonflower prints at 150 DPI by default, so pixels ÷ 150 = inches on the fabric: a 1500 px tile repeats every 10 in. For most print-on-demand products aim for 300 DPI at the size the pattern should repeat.
Is my pattern uploaded?
No. The checks, fixes and exports run in your browser. Your artwork never leaves your computer.
Sources
Checked on 29 September 2026.
- Spoonflower Help Center, Repeat Options — basic, half-drop, half-brick, center and mirror repeats.
- Spoonflower Help Center, Sizing Your Design — 150 DPI default; inches × 150 = pixels; 300 ppi files first show at double size.
Selling patterns on products? Also see the print-ready file checker.