Most of a map's loading time is its images. Because level images are stored at the full size you upload, a few sensible choices about format, resolution and detail are what keep your map loading quickly and panning smoothly — especially on phones and slower connections.
The biggest wins
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Use SVG for drawn maps
A vector map is usually the smallest file and stays sharp at any zoom — the best of both. Just keep the SVG tidy (below).
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Right-size raster level images
Level images aren't shrunk for you, so export JPG/PNG at a resolution that stays crisp at full zoom and no larger. A needlessly huge image just slows the first load.
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Pick the right format for the content
JPG for photographic maps, PNG for clean drawings, SVG for vector artwork. The wrong format can be several times bigger for the same quality.
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Trim empty margins
Blank borders are pixels a visitor downloads for nothing, and they shrink the useful part of the map on screen.
Keep SVGs lean
SVGs are stored exactly as you upload them, so their speed is down to the file. Simplify shapes, remove hidden or off-canvas objects, don't embed large photos inside the SVG, and run it through an optimiser (like SVGO or "Save as optimised SVG"). A tidy SVG can be a fraction of the size with no visible change.
Landmark images are handled for you
Photos, logos and thumbnails attached to landmarks are automatically scaled down when they're larger than about 1200 px wide, so a stray large photo won't wreck your load time. You still don't want dozens of unnecessarily heavy originals, but you don't need to hand-optimise every one.
Small settings that help
Where to look
| Lever | Where | Effect |
|---|---|---|
| Minimap image | Levels tab | A simplified minimap image is lighter than reusing a huge full map at corner size. |
| Animations | Settings → General | Turning off pan/zoom animation gives instant jumps, which can feel snappier on low-powered devices. |
| Number of level images | Levels tab | Every level is another image to load — keep each one right-sized. |
Check it on a phone
Preview your published map on an actual phone, ideally on mobile data rather than fast office wifi. If the first load feels slow, the level images are almost always the cause — revisit their size and format first.