Sharing a map
Three ways to share, chosen on the Map tab.
Standalone HTML — the default
One file. Everything is inside it: the map, its styling and all of its data.
Send it, copy it to a USB stick, put it on a shared drive. The recipient double-clicks it. They need a web browser and nothing else - no QGIS, no account, no internet connection.
It is the largest of the three, and that is inherent to the format. Every feature is written into the HTML itself, because there is no sibling folder for it to live in - that is exactly what makes the file self-contained. A map whose data runs to 20 MB produces a file of at least that size.
Nothing in a browser objects to a large HTML file. What objects is email: most providers reject attachments over about 20-25 MB, and corporate filters are often stricter. The Map tab shows your map’s data size next to this option, and warns before exporting if it is over the limit - you can still export the single file if you want it. To make it smaller, untick Popups on layers that do not need them, or reduce Coordinate precision on the Map tab.
Share ZIP
The same map, zipped, with a short README explaining how to open it.
Worth choosing even when the file is small: many mail providers and corporate
filters quarantine or strip .html attachments, because HTML is a common
phishing vector. A zip usually passes filters that a bare .html does not. If
someone says your map “never arrived”, try this.
Folder
For uploading to a web server yourself. You get a small index.html, the
OnlyMap runtime as a separate onlymap.js, and a README. Splitting them is the
point: a browser caches onlymap.js once and reuses it for every map on your
site, instead of downloading the same few megabytes inside every page.
This one does not open by double-clicking it. Browsers refuse to load the
runtime that way, so the folder has to be served over http:// or https://.
Use Standalone HTML if you want a file that opens straight off a disk.
Which to pick
| Situation | Use |
|---|---|
| Emailing it to one person | Standalone HTML, or Share ZIP if it is blocked |
| Posting it in a chat app | Standalone HTML |
| Attaching to a report or ticket | Share ZIP |
| Publishing on your own site | Folder |
What the recipient sees
An interactive map: pan, zoom, toggle layers, click a feature to see its attributes.
If they preview the file inside an email client or a file manager - somewhere that does not run JavaScript - they see a short message telling them to open it in a browser, rather than a blank window.