Aseprite Viewer Online — Open .aseprite and .ase Files
Someone sent you an .aseprite file, or an asset pack ships its sources that way, and Aseprite is not installed on this machine. Drop the file here: it is parsed inside this browser tab, every frame is composited the way Aseprite's own PNG export draws it, and the tags play on the Timeline.
- Aseprite JSONVerified· Phaser load.aseprite · PixiJS 8.21
- .asepriteVerified· Aseprite 1.3.18
- Godot 4Verified· Godot 4.7.2
- Unity 6Verified· Unity 6000.5.3f1
- Phaser 3 / 4Verified· Phaser 3.90 + 4.2
- PixiJS 8Verified· PixiJS 8.21
- Spine / libGDXVerified· spine-canvas 4.2
- Starling / Sparrow XMLVerified· Phaser 4.2
- LÖVEVerified· LÖVE 11.5
- DefoldBuilt· Defold bob.jar 1.13.1
- GameMakerUNVERIFIED
- CSS spritesVerified· Chromium
- GIF / APNGDecoded· Pillow
What it does
- Layers with all 19 blend modes, layer and cel opacity, groups, hidden and reference layers, cel z-index and linked cels, composited like Aseprite's export.
- RGBA, grayscale and indexed sprites, palettes that change per frame and the transparent index; tilemap layers drawn tile by tile with their flips.
- Tags with their direction (forward, reverse, ping-pong, ping-pong reverse) and repeat count, and each frame's own duration in milliseconds.
- Slices become Studio data: a slice named pivot, origin or anchor sets the pivot, other slices become hit, hurt, interact or custom boxes guessed from their names, and 9-patch slices keep their centre.
How to do it
- Drop the .aseprite or .ase file anywhere on the Studio.
- Read the Import panel: whether the layers were kept or flattened and why, and how each slice was mapped, each with a confidence.
- Press Enter to play the current tag; step with , and . and turn on onion skin (F3) or the floating preview (F7, up to 8×).
- Click a frame on the Timeline to see its duration, pivot and boxes in the Frame panel.
- To keep a copy in another format, open Pack & Export (PNG sheet with Aseprite JSON, a GIF or APNG per tag) or use Sprite › Export .aseprite… for a file Aseprite opens.
What the viewer reads from an .aseprite file
| In the file | What you see in the Studio | Checked against |
|---|---|---|
| Layers, groups, blend modes, opacity | Layer rows on the Timeline; flattened with a reason when they cannot be rebuilt exactly | Aseprite 1.3.18.6 frame exports: 231/231 files pixel-exact |
| Tags and frame durations | Tag lanes over the frames, milliseconds per frame; playback follows direction and repeat | Aseprite's scripting view: 231/231 files identical |
| Slices: pivot, plain, 9-patch | Frame pivot; hit / hurt / interact / custom boxes; 9-slice borders | 31 corpus files with slices |
| Tilemap layers and tilesets | Drawn into each frame tile by tile, flips included | 23 corpus files with tilemaps |
| Indexed and grayscale colour | Full colour, composited by index as Aseprite's PNG export does | 54 indexed and 13 grayscale corpus files |
ICC colour profiles are read and kept but not applied, which is also what Aseprite's PNG export does.
Engine exports and how each was checked
"Verified" means the exported files were loaded by the real engine or tool on real CC0 assets and the result was compared with the source. Anything that was not loaded is labelled as such.
| Target | Files | Check |
|---|---|---|
| Godot 4 | .tres SpriteFrames · .tscn AnimatedSprite2D · .png.import | Verified Godot 4.7.2Loaded by Godot; every animation frame drawn and compared with the source file. The scene uses Nearest filtering; rotation is never used. |
| Unity 6 | .unity.json · Editor/NerulioSpriteImporter.cs · AnimationClip | Verified Unity 6000.5.3f1Batch mode: sprite rects, pivots, pixels, clip keys and durations checked. |
| Phaser 3 / 4 | atlas JSON (multiatlas) · .anims.json | Verified Phaser 3.90 + 4.2Frames and animations drawn by both versions. |
| PixiJS 8 | spritesheet JSON · animations · anchor · meta.scale | Verified PixiJS 8.21Rotated and multi-page atlases included. |
| Aseprite JSON | hash / array · frameTags · slices | Verified Phaser load.aseprite · PixiJS 8.21Tags keep their direction and repeat count. |
| .aseprite | layers · tags · durations · slices | Verified Aseprite 1.3.18Opened and rendered by the Aseprite command line. |
| Spine / libGDX | .atlas | Verified spine-canvas 4.2Every region drawn by the Spine runtime, rotated and trimmed; libGDX itself was not run. |
| Starling / Sparrow XML | XML per page | Verified Phaser 4.2Phaser 3.90 draws trimmed XML frames wrongly (its own bug); the "Sparrow XML (Phaser 3)" preset turns trim off and passes in 3.90 and 4.2. |
| LÖVE | Lua quads · nerulio_atlas.lua · main.lua | Verified LÖVE 11.5Every frame drawn and every animation stepped through the shipped helper. |
| Defold | .atlas · .tilesource | Built Defold bob.jar 1.13.1Built by Defold's command-line builder; the built texture's UVs were read back. |
| GameMaker | spr_<name>_stripN.png · gamemaker.json | UNVERIFIEDNot loaded in GameMaker (no headless GameMaker). The strips are cut the way its strip importer cuts them. |
| CSS sprites | .css · preview .html | Verified ChromiumEvery class drawn from the shipped stylesheet. |
| GIF / APNG | one file per animation | Decoded PillowEvery frame and delay decoded again after export; APNG is exact. |
Evidence
GIF decoder: 408 of 408 frames identical to Pillow on 29 real GIFs; APNG 132 of 132 on 16 files. .aseprite: 231 corpus files imported, re-written and reopened in Aseprite 1.3.18 with the same tags, durations and pixels (231/231). Exports: 49 runs in the real engines on real CC0 assets, 47 pass — the 2 failures are Phaser 3.90's trimmed-XML bug, which the Phaser 3 preset avoids.
Limits
- A grid or island guess is a preview with a confidence; nothing is cut until you press Apply, and every choice has one-click alternatives.
- .aseprite files whose layers do not compose exactly (e.g. group opacity) are imported flattened, and the Import panel says why.
- Rotated frames in an imported atlas stay rotated; their export is UNVERIFIED.
- Images up to 32,768 px per side (268 million pixels), subject to your browser's memory.
Questions
Can I convert .aseprite to PNG without Aseprite?
Yes. Pack & Export draws the frames onto PNG atlas pages with an exact PNG writer (an indexed PNG when a page has 256 colours or fewer), next to the data file of the target you pick. For a moving picture, APNG keeps every pixel of each tag.
Why were my layers flattened?
Layers are kept only when composing them again gives exactly the pixels of the original. On the 231-file test corpus that held for 222 files; the other 9 (5 where group composition differs, 4 that use cel z-index) were flattened with the reason in the Import panel. The frames look the same either way.
Can opening the file here change my original?
No. The browser only reads it. A new .aseprite is written only when you choose Sprite › Export .aseprite…; files re-written that way were opened in real Aseprite 1.3.18.6, 231 of 231 without a warning, with the same tags, durations and pixels.
Is it free, and do I need an account?
Everything on these pages is free and works without an account. There is no watermark and no export that is held back.
Are my sprites uploaded?
No. The Studio decodes, packs and exports in this browser tab. Projects are autosaved in the browser (IndexedDB) and can be saved as a .nerulio file.
Does it need Aseprite or an engine plugin installed?
No. .aseprite files are read and written in the browser, and each engine bundle carries what that engine needs (for Godot, the import settings and scene; for Unity and the Godot TileSet, a small editor script).