GraphHopper Routing Engine
GraphHopper is a fast and memory efficient Java road routing engine released under Apache License 2.0.
Per default it uses OpenStreetMap data but can import other data sources.
All questions can go to our forum where we also have subsections specicially for developers, mobiles usage (iOS&Android) and our map matching component. Another place to ask questions would be on Stackoverflow but please do not use our issue section. Create new issues only if you are sure that this is a bug and see how to contribute in the next section.
Read through how to contribute
like finding and fixing bugs and improving our documentation or translations!
For the Web
See GraphHopper in action on GraphHopper Maps
GraphHopper Maps uses the Directions API for Business under the hood, which provides
a Routing API via GraphHopper, a Route Optimization API via jsprit, a fast Matrix API
and an address search via Photon. Additionally the map tiles from various providers are used
where the default is Omniscale, and all is available for free, via encrypted connections and from German servers for a nice and private route planning experience!
For Mobile Apps
GraphHopper supports several routing algorithms like
<a href="https://en.wikipedia.org/wiki/Dijkstra%27s_algorithm">Dijkstra</a> and
* and its bidirectional variants.
Furthermore it allows you to use
<a href="https://en.wikipedia.org/wiki/Contraction_hierarchies">Contraction Hierarchies</a> (CH) very easily, we call this
speed mode and in contrast to the speed mode we call everything without CH the
flexibility mode. BTW: This does not mean that the flexibility mode is slow.
The speed mode comes with much faster and lightweight (less RAM) responses and that although it does not use heuristics in its default settings.
The downsides are that the speed mode allows only pre-defined vehicle profiles (multiple possible in GraphHopper)
and requires a time consuming and resource intense preparation. And implementing certain features are not possible
or very complex compared to the flexibility mode.
You can use both modes at the same time.
We chose the Apache License to make it easy for you to embed GraphHopper in your products, even closed source.
We suggest to contribute back your changes, as GraphHopper evolves fast,
but of course this is not necessary.
OpenStreetMap is directly supported from GraphHopper. Without the amazing data from
OpenStreetMap GraphHopper wouldn't be possible at all.
Other map data will need a custom import procedure, see e.g. <a href="https://github.com/graphhopper/graphhopper/issues/277">Ordnance Survey</a>,
<a href="https://github.com/graphhopper/graphhopper/pull/616">Shapefile like ESRI</a> or <a href="https://github.com/knowname/morituri">Navteq</a>.
Written in Java
GraphHopper is written in Java and runs on Linux, Mac OS X,
Windows, BSD, Solaris, Raspberry Pi, Android, Blackberry and even iOS. Other
environments which supports at least Java 7 will work too.
We've build the GraphHopper class which makes simple things easy and complex things like multi-modal routing possible.
Still you can use the low level API of GraphHopper and you'll see that
it was created to allow fast and memory efficient use of the underlying datastructures and algorithms.
Android / Blackberry
On Android and Blackberry (since 10.2.1) we provide an integration with Mapsforge which makes offline navigation one step closer.
Due to the usage of memory mapped files and Contraction Hierarchies
we avoid allocating too much memory which makes it possible to run Germany-wide queries with only
32MB in a few seconds. We provide an Android studio project as well as the Maven-Android integration to be
used in other IDEs.
Web UI and API
With the web module we provide code to query GraphHopper over HTTP and decrease bandwidth usage as much as possible.
For that we use a polyline encoding from Google, the Ramer–Douglas–Peucker algorithm and a simple
GZIP servlet filter.
visualize the routes.
GraphHopper also runs on the Desktop in a Java application without internet access.
E.g. you could use the rough user interface called MiniGraphUI provided in the tools module, see some
visualizations done with it here.
A fast and production ready map visualization for the Desktop can be easily implemented via mapsforge.
Here is a list of the more detailed features including a link to the documentation:
- Simple start for users - just Java necessary! Simple start for developers due to Maven.
- Works out of the box with OpenStreetMap (osm/xml and pbf) but can be adapted to use your own data
- OpenStreetMap integration: Takes care of the road type, the surface, barriers, access restrictions, ferries, conditional access restrictions, ...
- GraphHopper is fast. And with the so called "Contraction Hierarchies" it can be even faster (enabled by default).
- Memory efficient data structures, algorithms and the low and high level API is tuned towards ease of use and efficiency
- Offers turn instructions in more than 35 languages, contribute or improve here
- Displays and takes into account elevation data (per default disabled)
- Can apply real time changes to edge weights (flexibility only)
- Customize vehicle profiles per request (flexibility only)
- Possibility to specify a 'heading parameter' for start, end and via points for navigation applications via
headingparameters (flexibility only)
- Alternative routes (flexibility only)
- Turn costs and restrictions (flexibility only)
- Multiple profiles and weightings (flexibility and speed mode)
- Several pre-built routing profiles: car, bike, racingbike, mountain bike, foot, motorcycle, ...
- The core uses only a few dependencies (trove4j and slf4j)
- Scales from small indoor-sized to world-wide-sized graphs
- Find nearest point on street e.g. to get elevation or 'snapp to road'
- Do map matching with GraphHopper (flexibility only)