How to Read The Gas Gauge
The lines on the gas gauge are increments of 1/4 representing your gas tanks fuel level. Anything between 2 lines would be an eight. If the needle were between 1/2 and 3/4, this would mean you have 5/8 of gasoline in your tank.
The line lowest to the bottom would mean you have 1/4 of a tank of gas and you should probably fill up soon, below 1/4 would be close to 1/8 of a tank which means get gas now. Newer vehicles have a low fuel light that illuminates and often come equipped with technology that informs you on how many miles you can proceed before running out of gas.
If the gas tank on a car holds 20 gallons of gas, and the gauge read "1/2", you have 10 gallons of gas. If your car gets 30 miles to the gallon, this means you can drive about 300 miles on a half tank of gas. Warning: Driving your vehicle on low fuel or an empty tank can damage your ride or even lead to a crash.
Now the fuel gauge in your car or truck is actually lying to you. Automobile manufacturers build in about a gallon (3.8 liters) of reserve fuel beyond the "empty" line. They also warn about low fuel long before a vehicle runs out, since they know that people procrastinate.
But those manufacturers are looking out for drivers: Running out of fuel can leave you stranded or cause a crash on the road, and can also damage expensive auto parts.