Set the map on the Map layer, size it by its intended square count, then align the Roll20 grid before touching tokens or fog. Roll20 uses a 70-pixel default grid cell, so a high-resolution source map does not need to stay at its full source pixel dimensions on the tabletop. Use Smart Sizing or Align to Grid when needed, stage tokens after the map is stable, and test the page from the player view last. Done in that order, most map setup problems disappear before the session starts.
You found a great battle map, uploaded it to Roll20, and placed it on the page. The grid is off by half a square in every direction, your tokens are the size of buildings, and the hidden areas are covering terrain your players should already be able to see. You have now spent 45 minutes on setup and the session starts in 20.
That is usually not a map problem. It is an order-of-operations problem. Roll20 gives you several ways to size and align a map cleanly, but the easiest workflow is to lock the page and grid first, then add tokens and visibility settings after the terrain is stable. This guide walks through that sequence, the settings that cause the most confusion, and the checks worth running before players ever join.
Why does your Roll20 map setup actually matter?
A misaligned map is not just ugly. It changes how the game plays. If Roll20's grid does not match the terrain underneath it, players cannot confidently judge movement, reach, spell areas, doorways, or cover. The DM ends up manually interpreting positions that the map was supposed to make obvious.
A clean setup does the opposite. Players drag tokens without asking where a square begins. Measurements make sense. Hidden areas reveal when you intend them to. The map becomes part of the interface instead of another thing everyone has to troubleshoot during combat.
If the table has to debate where the grid actually is, the map has stopped doing its job.
What resolution and file format should your map use?
Start with the source file, but separate source resolution from Roll20 display size. A map can be exported at 140 pixels per square, 100 pixels per square, or another high-resolution value and still line up perfectly in Roll20. What matters is that you know how many grid squares the map is supposed to contain.
Roll20's default square grid is 70 pixels per cell. If your source map is 140 pixels per square, that does not mean the Roll20 cell should also be 140 pixels. Size the map to the correct number of cells, or adjust Grid Unit Size only when you intentionally want a different display scale.
How do you import and size a battle map correctly in Roll20?
The easiest workflow is map first, tokens second, lighting last. Do not try to solve all three at the same time.
Switch to the Map layer before placing the image. You can upload through the Art Library or drag the file directly into the tabletop. If Roll20 detects a large image on a blank map layer, Smart Sizing may offer to adjust the page for you.
If the map is 30 squares wide by 20 squares tall, the displayed image should cover 30 by 20 Roll20 cells. Use Set Dimensions in units when available, or resize the page and image until the square count matches.
Move the map into position, align the grid, and confirm the full page before adding encounter pieces. Once the terrain is right, leave it alone and build the rest of the encounter on top.
How do you align the Roll20 grid to a map that already has a grid?
Use Roll20's Align to Grid tool before you start manually nudging every edge. On a gridded source map, zoom in, right-click the image on the Map layer, choose Advanced → Align to Grid, and trace a three-by-three-square area on the map's printed grid. Roll20 will resize the image to get the two grids close, and then you can fine-tune from there.
If the grid matches in one area but drifts farther out of alignment across the map, the issue is scale, not offset. Resize the image or adjust the grid unit size. If the spacing is consistent but every line is simply shifted, nudge the map while holding Alt to break grid snapping.
For gridless maps, setup is even simpler. Set the page to the intended square count, place the gridless image behind it, and let Roll20's overlay be the only visible grid. That removes the possibility of two line systems fighting each other.
Align the grid in prep. If you are eyeballing squares after initiative starts, you are spending table time on work that should already be invisible.
Black Lantern Forge maps are exported at high resolution with documented grid dimensions, so you can size them by square count instead of guessing at the canvas. Gridded and gridless versions give you the choice of using the map's grid or Roll20's overlay.
Browse Map Packs →How should you set up tokens before the session?
Token setup is the next source of avoidable friction. Wrong creature sizes, unassigned player control, and unstaged enemies are all simple problems when solved before the call starts.
| Creature Size | Grid Footprint | Pixels at 70px Grid |
|---|---|---|
| Tiny | 0.5 × 0.5 | 35 × 35 |
| Small / Medium | 1 × 1 | 70 × 70 |
| Large | 2 × 2 | 140 × 140 |
| Huge | 3 × 3 | 210 × 210 |
| Gargantuan | 4 × 4 | 280 × 280 |
What fog and lighting settings should you actually use?
Do this last. Visibility tools are much easier to configure after the page, grid, and token positions are stable.
Manual hiding and revealing is available without building a lighting layer. On Roll20's current tabletop engine this may appear as Hide / Reveal Mask; the Classic VTT uses the Fog of War name. It is fast, predictable, and ideal when you simply need rooms or unexplored areas hidden.
Plus and Pro games can use Dynamic Lighting for automated line of sight, barriers, night vision, and light sources. It is worth the setup on dungeons and indoor maps where walls matter. On open wilderness maps, manual hiding is often faster and visually sufficient.
The mistake is assuming more automation is always better. Dynamic Lighting can add atmosphere, but it also adds prep and can increase rendering load on complex pages. Use it when line of sight is part of the encounter. Skip it when the encounter is an open field and the lighting system would be doing work nobody at the table needs.
The map occupies exactly the intended cells
No drift from one side to the other
Correct size, character, and controller
GM layer until the encounter starts
Players can see exactly what they should
No hidden enemies or accidental reveals
What should you test before players join the session?
The most valuable final check is to look at the page as a player. Roll20 includes a Re-Join as Player option, and you can also use a separate browser profile or private window when you want a clean second view. The goal is simple: stop judging the page from the GM's omniscient perspective.
Check whether the correct areas are visible, whether any enemy token leaked onto the player layer, whether the grid contrasts enough against the art, whether player tokens begin in the right place, and whether movement feels natural at the zoom level your group will actually use. Problems caught here take seconds. The same problem discovered during a reveal or initiative roll breaks the scene.
Every later step depends on the earlier one being stable. If you change the map size after tokens or lighting are placed, you create more work than you save.
Frequently Asked Questions
Why is my Roll20 grid not lining up with my map?
If the grids are consistently shifted, the image is probably positioned incorrectly. Hold Alt while nudging the map so it can move independently of grid snapping. If the lines match in one area but drift farther apart across the image, the problem is scale. Use Align to Grid or resize the map until its intended square count matches the Roll20 cells.
What file size limit does Roll20 have for map uploads?
Roll20's April 2026 file guidance lists a 20 MB maximum image upload for Free accounts, 50 MB for Plus, and 100 MB for Pro. Storage caps are separate from the per-file limit. If a large map is difficult to upload or slow to load, a high-quality JPG is usually the easiest way to reduce file size without visibly hurting the map at normal play zoom.
Do I need to use 140 pixels per square in Roll20?
No. Roll20's default grid cell is 70 pixels, and its own map-export guidance treats 70 pixels per cell as directly compatible. A 140-pixel-per-square source map can still look excellent because the source resolution and the tabletop display size are separate. Match the map's square count to the Roll20 page rather than forcing Roll20 to preserve the source image's original pixel dimensions.
How do I stop players from moving tokens they should not control?
Make sure only the intended character is assigned to that player and that the token's control settings do not include players who should not move it. Enemy and NPC tokens should remain under GM control unless the encounter specifically calls for a player to control them.
Do I need a paid Roll20 account to use battle maps effectively?
No. The core VTT, map uploads, manual hiding and revealing, tokens, and turn tracking are available without Dynamic Lighting. Plus and Pro add Dynamic Lighting and larger storage and upload allowances. Upgrade when those features solve a real problem for your table, not because basic map play requires them.
How do I switch between maps quickly during a session?
Create each encounter as its own Roll20 page before the session. Stage the map, tokens, and visibility settings on that page in advance, then move the party to the page when the encounter begins. The transition feels instant because the setup work already happened.
Why do my tokens look blurry on Roll20?
Blurry tokens usually start with a source image that is too small or heavily compressed. Roll20 recommends PNG for token art because it preserves transparency and edge detail well. Start with a square, sufficiently high-resolution token source and let Roll20 scale it to the correct number of grid cells.
Can I use Black Lantern Forge maps directly in Roll20?
Yes. Use the grid dimensions listed with the map to size the Roll20 page, then place either the gridded or gridless file on the Map layer. With gridless files, Roll20's overlay can be your only grid. With gridded files, use Align to Grid if the printed lines need a final adjustment.
High-resolution, VTT-ready battle maps with documented grid dimensions, gridded and gridless options, and layouts built to stay readable once tokens hit the table.
Shop Battle Map Packs →Sources
| Roll20 | Sizing and Aligning Maps |
| Roll20 | Best Practices for Files on Roll20 |
| Roll20 | Token Features |
| Roll20 | Fog of War / Hide and Reveal Mask |
| Roll20 | How to Set Up Dynamic Lighting |
