Getting rejected at upload time is frustrating, and the usual cause is a file that does not match LINE’s size or format rules. This guide lists the numbers that matter and shows how to produce them reliably.
The core sticker size: 320 × 320
Every standard LINE sticker must be a 320 × 320 pixel PNG with a transparent background. The image should sit centered with a little padding so important details are not clipped on small screens. LINE displays stickers in a roughly square area, so filling the full 320×320 edge-to-edge is fine, but leaving breathing room usually looks better.
The two companion images
When you submit a sticker set, LINE also asks for two small images:
- main.png — 240 × 240. The thumbnail shown in the sticker shop and chat sticker panel.
- tab.png — 96 × 74. The tiny icon in the sticker tray. It is wider than it is tall, so center your art horizontally and leave vertical padding.
Both should be transparent PNGs derived from your main artwork. The HailouTec cutter can generate main.png and tab.png for you when “LINE spec” is enabled, so you do not build them by hand.
Other sizes you may meet
- Header / cover — 975 × 500. The banner at the top of your sticker set in the shop.
- Animated stickers — up to 320 × 320, 50 KB cap per frame (APNG). Tighter limits apply than static stickers.
- Popup stickers — up to 480 × 480. Larger art that appears when tapped.
Setting up your artboard the right way
1. Start at 320 × 320
Design each sticker on a 320×320 canvas with transparency. Working at the final size avoids blurry scaling later.
2. Keep it transparent
Do not fill the background with white. LINE uses the alpha channel to composite stickers over chat bubbles; a white box will look wrong. If your source has a white backdrop, use a background-removal step (see the transparency guide).
3. Watch the file size
Static stickers must stay under 1 MB each; animated frames are capped much lower. Oversized files are the second most common rejection reason after wrong dimensions. Compress without flattening transparency.
4. Export as PNG
PNG preserves both the crisp edges and the transparency that LINE requires. JPEG will fill the background and is not accepted.
Common mistakes
- Square-but-wrong: a 300×300 or 500×500 image is still rejected. It must be exactly 320×320.
- White background: looks fine on a white chat, but wrong everywhere else.
- Forgetting tab.png ratio: a 96×96 square gets stretched in the tray. Use 96×74.
- Oversized file: even a perfect 320×320 PNG fails if it exceeds 1 MB.
Fast path with the cutter
Instead of resizing in an editor, split your sheet, tick “LINE spec”, and the tool outputs each sticker at 320×320 plus the matching main.png and tab.png, centered and transparent-ready. You then only need to add the 975×500 header before submitting.
Want the companion guide? Remove a white background while keeping transparency →