Route Calculations


As a proud owner of a "new" driveluxe 50, of course I am comparing waze, google maps, and my garmin.

I've noticed a few things in routing my well known path.

1) As a default, my garmin will route me through the downtown core with a lot of traffic lights.
Garmin 10min
Waze, google 11min

2) my normal route is the route that waze and google pick.
Garmin 11min
Waze, google 9min

No #2 would explain why my garmin is sending through downtown as that route is calculated at 10min.

Anyone understand why the descrepany in route times? Wouldn't both know the speed limits?
I have navigation set for faster time instead of shorter distance



Each device/system can vary simply due to different routing algorithms, map detail, traffic info etc. If you're expecting them to all be the same you'll be waiting a long time wink

Where there's a will ... there's a way ... DriveSmart50LMT-D, Nuvi 2508LMT-D, 1490LMT, 1310, Montana 650T, Etrex 20

My experience has been,

My experience has been, Garmin assumes you will be traveling the speed limit and will have all green traffic lights.

Any difference between

Any difference between Shortest Route and Fastest Route setting.

I never get lost, but I do explore new territory every now and then.

not the speed limits

eclindholm wrote:

Wouldn't both know the speed limits?

Part of the map database is an estimate for each segment of road as to the likely rate of advance. That number is not generally the speed limit. For one thing, for lots of pieces of road the device does not know the speed limit. If you happen to own one of the Garmin devices which display the speed limit when known, you can see that point for yourself.

Furthermore, at least some of the Garmin devices adapt the estimated rate of advance based on things they think they have learned from observing your driving.

For me in Albuquerque the net result is that Garmin estimated travel times within town are generally remarkably close to the truth (and much closer than those from Google Maps). On the other hand the highway numbers are pretty generally fairly bad. Possibly this is partly because it has spent a lot more time watching me drive in town than on highways.

personal GPS user since 1992