Web App For Calculating And Tracking Your Gas Mileage


Limp Gawd
Feb 1, 2008
You don't necessarily need to drive slow. Remember that you get better mileage on the highway than in the city. You need to drive steady, and I suppose accelerate at a decent amount.

New cars are getting lighter, not heavier. They are always looking at getting lighter materials for the body.

My 1990 Protege was 2300 lbs, my 2005 Corolla is 3200. Both have about the same sized engine, both manual tranny and both got/get a combined 32mpg around town with the AC on being driven by both a sedate mom and a leadfooted dad.

My pigmobile T&C with a 3.8l V-6 got 22mpg on a 3000 mile roundtrip to Colorado from Texas last year and clocked in a 16mpg roundtrip up Pikes Peak. Getting 20 around town by coasting a lot.


Apr 7, 2005
Use it for every tank of gas, for each of my vehicles, without fail. It doesn't just do the math, it also tracks over time, shows charts & graphs, converts between metric and US measurements (no Imperial yet though), and allows you to compare real world mileage among vehicles.

It was a great tool to use when I was recently car shopping - I could see what mileage people were actually getting from the vehicles I was considering.

Yes, my vehicles have trip computers with mileage displays (amazingly inaccurate), I know how to do math, and I know how to make a spreadsheet. Fuelly is exactly what I need though.

86 5.0L

Supreme [H]ardness
Nov 13, 2006
You used Mustangs as an example in a fuel economy thread? Seriously?

Why does it matter? Take any vehicle with a decent production history, they all get fat

Btw, I like getting 27MPG in my $200 Mustang GT


Extremely [H]
Oct 29, 2000
#2 If you wanna get anywhere near the rated MPG, you'll have to drive slow. I don't have the patience as it is.

Also, it's not necessarily required to drive slowly to get decent mileage. (within reason at above 80mph aerodynamics really starts to become a problem)

The key is to drive in fluid motion. Nothing jerky. No harsh acceleration or sudden stops.

Learn to view the brake as a "waste pedal" and drive in a way such that you use it as little as possible. Whenever you use the brakes you are scrubbing off useful kinetic energy, which either means you will have to regenerate it again (by burning fuel) or you generated too much of it already (by burning too much fuel)

Again, this doesn't necessarily mean driving slowly. Drive fast but - as an example - leave lots of space between you and the person ahead of you, so that if they slow down, you don't have to slam on the brakes, you can just coast.

Fluid motion is the biggest key to fuel economy (and it usually leads to safer driving too) without significantly impacting travel times.

In my recent trip from Boston to Harford (~100 miles) I averaged almost 30mpg on the way there, maintaining a speed of approximately 85mph in my 3450lb mid sized Saab 9-5 with a tuned 300hp 2.3L turbo engine. This was accomplished by just driving as fluidly as possible, and still keeping relatively high speeds.

(on the way back, I averaged about 38mpg by both driving fluidly and slowing down as I was tired and not in a hurry)