Rounding pixels per square
Foundry accepts decimals, but 68.5 px grids drift on large scenes. Export whole-number multiples instead.
VTT guides
Export Battle Maps for Foundry VTT
Export a grid-accurate PNG from RPG Map Editor, set it as a Foundry scene background, and align the scene grid in minutes—then build walls, lights, and tokens where they belong: inside Foundry.
Quick answer: Export a PNG from RPG Map Editor whose width and height are multiples of your pixels-per-square value, place it as a Foundry scene background, then set Foundry's grid size to the same pixels-per-square and shift the origin until squares track. Walls, doors, and lighting are added inside Foundry—RPG Map Editor does not export them.
Recommended export settings
PNG dimensions Foundry can use cleanly
Formula: export width = columns × pixels per square, export height = rows × pixels per square. Divisible dimensions are what keep Foundry's grid from drifting.
| Map size (squares) | At 70 px/sq | At 140 px/sq | Good for |
|---|---|---|---|
| 20 × 20 | 1400 × 1400 px | 2800 × 2800 px | Taverns, single rooms |
| 30 × 20 | 2100 × 1400 px | 4200 × 2800 px | Roads, camps, medium fights |
| 40 × 30 | 2800 × 2100 px | 5600 × 4200 px | Arenas, set pieces |
Need different numbers? The D&D battle map size guide includes an export-resolution calculator.
Workflow
Step-by-step import into Foundry
- Finish the map in RPG Map Editor. Terrain, props, and (optionally) a light baked grid.
- Export PNG at columns × pixels-per-square. Note the two numbers—you will reuse them in Foundry.
- Create a scene in Foundry and add the PNG as the background image.
- Set grid size in scene configuration to the same pixels-per-square value used at export.
- Add walls, doors, and lighting with Foundry's own tools once the background sits right.
Grid alignment
Get the scene grid to track the art
- Match numbers first: Foundry grid size in pixels = the pixels-per-square value you exported with.
- Then adjust origin: shift the grid offset until squares land on the art—one corner is never enough; check all four plus center.
- Watch padding: if the image has a border margin, pad the scene dimensions identically so cells stay square.
- One grid only: prefer a light or absent baked grid and let Foundry draw the play grid.
Pitfalls
Common mistakes
Aligning walls before the grid
Draw walls only after the background and grid are final—otherwise every wall is off by the same offset.
Skip-checking corners
A grid that looks aligned at the start of a corridor often drifts by its end. Verify across the full map.
Limitations
What this workflow does not do
- No Universal VTT (.uvtt) export. Treat richer metadata formats as planned unless they appear in the shipped product.
- No wall, door, or lighting data. The PNG carries pixels only; Foundry owns everything simulation-related.
- No direct upload. You save the PNG and import it through Foundry's asset files yourself.
FAQ
Foundry VTT export FAQ
What map size works best in Foundry VTT?
Foundry is flexible: set your scene grid size to match the artwork. Export a PNG whose pixel width and height are multiples of your intended pixels-per-grid-unit so scaling stays predictable.
Does RPG Map Editor export Foundry walls or lighting?
Not today. The workflow is PNG import into Foundry; configure walls, doors, and lighting inside Foundry after the image is on the scene.
How do I align the Foundry grid to my map?
Create a scene with the image, open grid configuration, match cell size in pixels to your export math, then shift the grid origin until it tracks the printed grid in the art.
Is WebP or PNG better?
RPG Map Editor’s export path discussed here centers on PNG for broad VTT compatibility. If you convert formats, verify transparency and sharpness after conversion.
Related guides
Size the map before export, check the Roll20 workflow, or start a new encounter map.