A planning and analytics suite for Subway Builder. It reads the game's real demand grid and live line metrics to show where to expand, which lines need trains, when, and where crowding comes from.
Network Planner adds a three-tab panel alongside the game. The analysis works with zero setup: no dependencies, no account, no key.
- Walk catchments with a real coverage percentage of residents and jobs actually within reach.
- Mode-shift potential: drivers whose home and work are both reachable. Your genuinely winnable market, not a vanity number.
- A ranked "Build here next" list of the biggest unserved markets. Click a row to fly straight there.
- Per-route and per-station riders versus drivers, with success-rate dots on the map.
- Per-line Load Factor with plain-English advice (Add peak trains, Trim off-peak, Over-served, Rising or Easing vs yesterday, Balanced).
- Load-by-hour charts showing exactly which hours each line overcrowds, with a day-over-day comparison, a current-hour marker, and the game's High/Medium/Low service brackets marked.
- Expand any line for its crowding contributors, the busiest boarding stops. Click one to fly there.
- Remembers your data per save, so it is never blank on reload.
Layer toggles, key-free satellite imagery (Esri, Google, Hybrid, OSM), opacity, and station-dot size, plus an inline glossary explaining every concept.
| Term | What it means |
|---|---|
| Coverage % | Share of the whole city's residents (and jobs) within walking reach of any station, counted once. |
| Catchment | Each station's walk circle, about a 30-minute or 1.8 km walk. The area people can reach on foot to or from the station. |
| Mode-shift potential | Drivers whose home and work both fall within a catchment. The riders you can win on today's network. |
| Latent demand | Would-be riders who drive today and whose other trip end is already on your network, so one extension wins them. Dot size is how many; dot color is distance to your nearest station (green means build now, red means a corridor to grow toward). |
| Station transit share | Of the motorized commuters near a station, the share who already ride instead of drive (the dot's percentage and color). Low means lots of nearby drivers not yet won. |
| Load Factor | riders/hr divided by (trains/hr times train capacity). Shown as the rolling average across the day; the status uses the peak hour, so rush overcrowding is never hidden. |
| vs yest | Day-over-day change in a line's average load. |
| Crowding contributors | The busiest boarding stops on overcrowded lines, where to add trains or build a relief line. (Boardings are where demand originates; the game does not expose on-board segment occupancy.) |
Install the Railyard mod manager and search for "Network Planner".
- Create a
network-plannerfolder in your mods directory (Main Menu > Settings > Mods). - Download the latest ZIP from the releases page.
- Extract the ZIP contents into the
network-plannerfolder. - Restart the game and activate Network Planner.
The Planning and Efficiency tabs work immediately. No setup, no dependencies, no key.
Satellite is the only feature that needs anything extra. The game blocks external tile domains, so tiles are served from a tiny local proxy on 127.0.0.1. It requires Node.js. All four providers are key-free.
macOS, run once and it auto-starts at login:
bash install-proxy.sh(from the mod folder; remove with bash install-proxy.sh --uninstall)
Windows, register once:
schtasks /create /tn NetworkPlannerSatProxy /tr "node \"%APPDATA%\metro-maker4\mods\network-planner\proxy.js\"" /sc onlogon /fAny OS, each session:
node proxy.jsThe Setup tab shows whether the proxy is connected and guides you if it is not.
Provider note: Esri World Imagery and OpenStreetMap are licensed for use; the Google endpoints are unofficial, fine for personal play, which is why Esri is the default.
Bug reports and ideas are very welcome.
- Found a bug? Open an issue with steps to reproduce and your game version.
- Have an idea? Open an issue to discuss it before sending a PR.
| Subway Builder | subwaybuilder.com |
| Official API docs | subwaybuilder.com/docs |
| Community modding | subwaybuildermodded.com |
MIT, 2026 David Karpik.