# Share a Folium Map — A Live Leaflet Map on a Link

Canonical: https://commareports.com/share-folium-map
Published: 2026-08-23

> m.save('map.html') gives you a pannable Leaflet map that only you can open. Publish it to Comma for a URL where the map still zooms, the markers still pop, and a colleague can comment on a cluster.

# Share a Folium map

A Folium map is one of the friendliest things Python can produce and one of
the least shareable. `m.save("map.html")` writes a working Leaflet app; then
it sits in a working directory, and the person who needs it gets a screenshot
of the map at exactly one zoom level — which is to say, none of the map.

## Publish it

```python
import folium, requests, os
from folium.plugins import MarkerCluster

m = folium.Map(location=[40.71, -74.01], zoom_start=11)
cluster = MarkerCluster().add_to(m)
for row in sites.itertuples():
    folium.Marker([row.lat, row.lon], popup=row.name).add_to(cluster)

m.save("map.html")

requests.post(
    "https://commareports.com/api/v1/reports",
    headers={"Authorization": f"Bearer {os.environ['COMMA_API_TOKEN']}"},
    json={"title": "Service coverage — NYC", "html": open("map.html").read()},
).raise_for_status()
```

Folium's generated file pulls Leaflet and its plugins from jsdelivr and
cdnjs — both allowlisted for scripts inside report HTML — and tiles are plain
image requests, allowed from any HTTPS origin. So the published map pans,
zooms, clusters and pops exactly like the local one.

## What the URL changes

- **The reviewer explores instead of squinting.** Zoom to their own borough,
  check their own site.
- **Comments pin to context.** Wrap the map in a short brief — what changed,
  what decision is pending — and the discussion anchors to that text. See
  [commenting on HTML](/comment-on-html).
- **A map per week, one URL.** PATCH the same report id and coverage drift
  becomes a revision history instead of a folder of dated files.

## Keep the key quiet

If you use a paid tile provider, the token is embedded in the tile URL —
that is true of any static Leaflet export. Publish with a domain-restricted
key, and keep the report **private or team-visible**; see the
[sharing model](/docs/sharing). Reports are private by default.

## Limits

- **HTML body: 5 MB.** Cluster or aggregate before saving; raw marker arrays
  are the usual culprit.
- **Scripts run, sandboxed:** `allow-scripts`, no `allow-same-origin`.
- **60 requests/minute per token.**

## Try it

Comma is free — unlimited reports, unlimited commenters, unlimited revision
history.

**[Publish a map →](https://commareports.com/)**

### Related

- [Share a Plotly chart](/share-plotly-html) · [Share a Bokeh plot](/share-bokeh-plot)
- [Interactive HTML reports](/interactive-html-reports)
- [EDA reports](/share-eda-report) · [Scheduled reports](/features/routines/scheduled-html-reports)