Google Maps Accuracy
 

Any of you all use google maps? I'm wondering how accurate it is from a time perspective. It says my commute would be about 13 miles and a ride of about an 1:20 or so. I'm just wondering if I could reasonably meet those numbers or if I would need to adjust.

Google maps assumes a fairly slow speed, I think it was about 11 or 12 mph. I always beat their times.
For example, my commute home is shown on Google Maps to be about 43 minutes, The slowest I do it is 35 minutes and cruising speed is around 15-17mph
I think anybody in reasonably decent shape shouldn't have too much difficulty meeting those numbers

I'm not sure, but to me, it seems they estimate movement at 10 mph for cycling. I do a little better than that, so I beat those times. The exceptions are when it's a long ride and I need rests. Google doesn't expect you to rest, so in those cases, I do worse than the time estimate.

But with all of that said, I find it to be an excellent estimator of travel time, for cycling, walking, mass transit, and car driving. I use it for all of those modes.

In terms of distance, Google Maps is very accurate. In terms of time, terrain impacts their calculation but the rate is otherwise fairly low.

google maps says my route home from work is 7.8 miles and 44 minutes cycling time for a 10.6 mph overall average.

i can usually do it in about 35 minutes (assuming neutral wind conditions) for a 13.4 mph overall average.

Now if they had a place to put in your average speed then that would be more accurate. like I check google maps to get home it shows 9.5 miles in 49 minutes but I do it in 32 to 35 minutes. ok a good day I do 18 to 19 mph thats about 22mph on the flat.

There's an estimated 10-11 mph that the app uses.

For level ground, I'm always faster than their estimated time. There a couple of routes I do with a lot of climbing that I'm usually a little slower.

For cars it is pretty aacurate and also takes traffic into account. It also updates dynamically based on actual speed or new traffic information. All the other google users's phones send data on their speed, which is how google knows current traffic. You also can enter a different time, like rush hour, and it will estimate a different duration. Pretty cool, and fairly correct.

Obviously a car engine is always able to drive at legal speed. The physical ability of the engine isn't relevant for estimating duration.

For human powered modes like walking and riding, they only can estimate the speed. What do you expect? Someone from Google measuring your FTP, your aerodynamics, weight and mood?

I've found it pretty good. It's including estimates for stoplights etc.

My commute is fairly level so I don't know how well it might do with a grade

Google Maps is pretty good - when it's working.

I don't have a data plan, so sometimes even my downloaded map is just a grey screen with a blue dot on it. So I have to remember to turn the map on when I still have wifi before I go.

While travelling, I do have a data plan and sometimes that blue dot just keeps jumping around different streets even when I'm just standing still.

I suggest you set the best way for you

If I need a good estimate, I use Strava. That uses my actual average speed.

I cruise around 20mph, so to use google maps, 2/3 of their estimated time is fairly accurate for me. But Strava nails it.

I never actually tried using strava to make my route to work but you're right, it's dead on.

Google maps assumes a very slow speed. I always beat its estimates.

Just be careful if you use it to plot a route. It will send you down some roads that are not really bike friendly.

I didn't realize it figures in stops, interesting

I use a simple Speed-Distance-Time calculator (https://www.calculatorsoup.com/calcu...calculator.php) and input the avg. speed I think I'l be doing that day, based on whether it'll be the road bike, commuter, mtb, and if I'll be hammering, or doing a slow recovery ride, and how much climbing will be occurring, as well as wind direction if it's just a point-to-point ride, so anywhere from 11 mph to 21 mph, which changes ride duration dramatically.

If I know I only have 2.5 hours to ride, I can use the calculator to tell me how many miles I can fit in, by inputting that time and my avg speed, and then think about a route of that length.

It would depend entirely on how fast you ride. Do the math to figure out what google thinks the average speed is, then compare it to your average speed.

Ill do the math for you since you are asking this question. 1 hour 20 min = 80 minutes. 13 miles into 80 minutes is .1626 mile per minute. multiple .1626 by 60 minutes to figure out miles per hour. 9.75mph.
So do you ride faster than 9.75mph? If you do, then no it isnt accurate. If you ride slower than 9.75mph, then no it isnt accurate.

As a commuter, I beat that Google Maps Cyclist every time. He's slow.

And as a long distance rider, same thing up to a point. 125 miles is about 10 hours for me, well ahead of Google. But as the distance goes up, Google Maps Cyclist catches up. My longest "day" in the saddle was just under 300 miles, which took me 27 hours (that's a "day", right? :lol:), just ahead of Google. At that point, I had to shower, eat, sleep... But Google never sleeps. By the time I got up, Google Maps Cyclist was way ahead.

Google Maps Cyclist does 1200 km in 67 hours. Ask any Randonneur, s/he will tell you 67 hours is very impressive indeed. Hardcore. I've never done a 1200 in less than 86 hours.

I won't comment on time accuracy since that's like estimating how long a marathon takes.

As far as accuracy goes, I wouldn't take their elevation profiles too seriously since it seems to significantly under estimate total ascending and descending elevations. The net elevation change might be accurate but the rides are usually tougher than the elevation profile indicates.
I used to take the url of the ride and convert it to a GPX using www.gpsvisualizer.com. Both google earth and Delorme Topo showed significantly more ascending elevation than google maps did. You can no longer use gpxvisualizer to do this without jumping through some hoops, but mapstogpx.com seems to work. Gpxvisualizer uses the Digital Elevation Model (DEM) which I believe is what google uses so I'm comparing the same basic data.

Suggestion...Why not do the route on a weekend or day off. Adjust for expected traffic on your actual commute days and you'll know true time and distance.

There are several sites out there that do a slightly better job than Google, at the cost of convenience and speed. Strava uses your own history over the route, if you've taken it, and http://cycle.travel can compensate for hills if you haven't. But it's not like taking your car and wondering how long it will take your car to drive to a destination 800 km away. The app Osmand also works well if you don't have a data plan for local trips.