On line map milage compared to actual miles

I've often wondered if the distance between two points on a map is based on a flat surface, because the map is flat. Actual driving, going up and down hills could be much farther between those same 2 points. If the distance (as the crow flies) between 2 points is 100 feet (looking straight down), the actual distance on the ground could be 101 feet, taking into account an incline between the same two points. It's possible the mapping system does not take the actual ground surface. But ... I could be wrong too. I'm just guessing?

Intresting question. I know of several roads of more that 50 miles on which the distance between two point has a measurable difference depending on which way you are going. Its also more difficult to drive from Memphis to Knoxville because its uphill most of the way, and viceversa.

AH64ID wrote:
How much of an error are you talking about?

Being nobody else has the problem so it must be me. I'm just going to watch it more closely.

Can't believe how long of drive it turned out to be. We went from Yuma to Bakersfield, Google maps says 382 miles in 6 hours 6 min.

That's somewhat long for us as prefer 200-300 miles a day, but didn't want to overnight anywhere so we decided to drive it in one shot. LA traffic was a big delay (starring at cars in front of us). And grapevine was messed up because of something, so we went thru Lancaster and Mojave down thru Tehachapi to Bakersfield. Stopped a couple of times to eat and fuel up. All said and done the 6 hours and 6 min drive turned into little over 12 hours.

We keep a log (somewhere) of fuel and mileage, but I'm going to start keeping track of our mileage at beginning of the day to get a better feel of what is best for us. (Step one is finding the thing)

I'm glad people chimed in and got me straight on this. I thought maybe the on-line maps showed "air miles" and not actual miles on the ground travel.

How much of an error are you talking about?

path1 wrote:
OK thanks folks...Most be me. I'll explore more into what I might be doing wrong. I can see being off when you get directions from city to city and not street address to street address.

Last time I checked my ODO on dash is right. Example: when doing 60MPH I get 1 min per mile.

How do you know you are actually going 60MPH? Maybe your speedometer isn't accurate? Check against an accurate source.

OK thanks folks...Most be me. I'll explore more into what I might be doing wrong. I can see being off when you get directions from city to city and not street address to street address.

Last time I checked my ODO on dash is right. Example: when doing 60MPH I get 1 min per mile.

the bear II wrote:
I have found the mileage in most mapping programs to be very accurate.
You can check your odometer by using a GPS navigation system in your vehicle or mapping APP on a smartphone. These programs accurately show miles traveled and speed in real time.

X 2

I have found the mileage in most mapping programs to be very accurate.
You can check your odometer by using a GPS navigation system in your vehicle or mapping APP on a smartphone. These programs accurately show miles traveled and speed in real time.

Every time I use the path tool on google earth I am amazed how close it is for a known route. Even when I average between the curves, it doesn't seem to matter much.

path1 wrote:
I notice a difference of actual miles driven compared to what google maps says the mileage should be.

Is it just me or is there any settings I need to change?

Anybody else notice this? What is your work around?

Thanks

Stop swerving so much. :)

Are you sure your odometer is accurate?