This tool is free to use. Please don't abuse it; it has limited API calls for now. If you feel like dropping a tip, or buying some merch, I won't stop you.
This tool was designed to aid in planning and establishing repeaters. It calculates line of sight, realistic coverage at each node, and even helps plan a network of nodes to cover significant distance.
This tool does not use existing repeater data. Published repeater lists are unreliable: locations are often unverified, and listed repeaters may no longer be on the air. Add the repeaters you know about as nodes.
Works on a phone, but best on a computer or tablet, where the map and charts have room.
Chain checks each node against the next one in the list, like a planned repeater route. Reorder with the arrows in Nodes.
Mesh checks every pair of nodes, the way the network really works. With many nodes it draws a lot of lines and takes longer.
Coverage shades where all your nodes combined should be heard. More coverage options ↓
| Link | Status | Distance | Lowest clearance | Fresnel clear | Path loss | Est. signal | Est. margin |
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Chain is easier for planning a path; in Chain, the order here is the order of the route. Mesh is how the network actually works: any node can talk to any other it can hear.
Shades where your nodes should provide coverage, factoring in terrain, trees, distance and realistic radios. It updates by itself when you change nodes or settings.
Looks for high points along a driven route or a straight line between two points, then picks repeater sites: either the strongest chain linking the two, or the set that covers the most of the drive.
Suggested sites are picked from terrain and road access only: they don't account for private or public land, gates or permission, so check ownership before you plan on a spot.
Limits. One search adds up to 10 repeaters, each hop no longer than your max hop length, so it can span about 11 hops at most (275 miles at 25-mile hops, usually less since peaks rarely line up). Longer searches use coarser terrain and more road data, and very long corridors can be too much for the road service. For long trips, work in legs: add nodes at towns or passes along the way and search one leg at a time, about 50 to 150 miles each.
Verdicts. The color says whether a link should work. Clear (green): at least 60% of the Fresnel zone is free of terrain and trees, with 10 dB or more to spare. Should work (yellow): the estimate has signal to spare, but the path is partly or fully blocked, or the margin is thin. Unlikely (red): the estimate falls short. The stats also show the line of sight on its own (clear, partly blocked or blocked). LoRa can bend over a ridge, so the signal estimate adds a loss for the main ridge and the worst ridge on each side (the Deygout method).
Limits. Elevation data is mostly bare ground, so set the tree height in forest. Real links vary by several dB from the estimate, and paths over many ridges can be worse. Treat results as a planning guide and confirm with a field test.
Chain vs. Mesh. Chain checks each node against the next in the list, like a repeater route; reorder with the arrows. It is the easier view for planning a path. Mesh checks every node against every other, which is how the network actually works: any node can relay for any other it can hear, so it shows direct links and backup paths.
Node Coverage. Rays from the node are checked against the terrain, and each spot pays a diffraction loss for up to three ridges in the way (a multi-ridge method similar to the one the Line of Sight links use), plus the trees and realism penalty. Expect less in dense forest and among buildings.
Route finder. Candidates are local high points inside the corridor and within your distance of a road (OpenStreetMap). "Follow the road" uses the fastest driving route from OSRM. Links between candidates are screened on coarser terrain (about 30 m, coarser on long searches), so after "Use these nodes", the Line of Sight block rechecks them at full detail. It knows nothing about gates, closures, land access or private property; check every site on the satellite layer and in person.
Glossary. dB: a ratio scale for signal strength; every 6 dB is double (or half) the range in open country. dBm: power relative to one milliwatt (22 dBm is about 0.16 W). Margin: signal to spare above what the receiver needs. Line of sight: an unbroken straight line between antennas. Fresnel zone: the space around that line the signal actually uses. Diffraction: radio bending over a ridge, at a cost of several to tens of dB.
Map tiles: Esri, OpenTopoMap. Driving routes: OSRM demo server (OpenStreetMap data; light, non-commercial use). Roads: © OpenStreetMap contributors, via Overpass API. Elevation: Terrain Tiles on AWS Open Data (Mapzen; USGS 3DEP about 10 m in the US); fallback USGS 3DEP 10 m via OpenTopoData (1,000 requests a day) and Copernicus GLO-90 via Open-Meteo.