Easy Guide to Check and Improve Your Car's Mileage

Updated on 2 Jan 2026

When you plan to buy a car, one of the first things you have to consider is the mileage. It tells you how far the vehicle can travel in one litre of fuel. Knowing how to calculate your car’s mileage is very important for saving money, planning long trips and keeping your vehicle in good condition.

In this guide, we will explain the steps to calculate the mileage of a car.

What is car mileage?

Mileage is the distance your car can travel with one litre of fuel. It is usually represented in kilometres per litre (km/l). For example, if your car travels 15 kilometres with 1 litre of petrol, then its mileage is 15 km/l.

Mileage is one of the most important factors for car owners in India, where fuel costs are high. A higher mileage means you spend less on fuel, while lower mileage means higher expenses.

How to calculate your car's mileage?

Here is how to calculate the mileage of a car:

Fill up the fuel tank

First, ensure that you fill your car’s fuel tank entirely, taking note of the quantity added in litres. This step is crucial for obtaining the most precise fuel consumption and mileage measurement.

Check the reading of the odometer

Note the current odometer reading before you start driving. Then, drive your car normally for a few days or at least until the fuel level drops noticeably. Record the new odometer reading when you next refuel. Subtract the initial reading from the new one to find the total distance travelled.

Refuel and note the amount of fuel

When you refill your tank, note how many litres were added to reach full again. This amount represents the fuel used for the distance you travelled.

Do the math

Calculate the car mileage using the formula:

Mileage = (Second reading on odometer - First reading on odometer) /Number of litres of fuel filled

 or

Mileage (km/litre) = Distance travelled (km) ÷ Fuel used (litres)

Let us say you go on a road trip with your four-wheeler. Before starting, the odometer reads 20,000 kilometres, and you fill the fuel tank with 40 litres of fuel. After completing your journey, you check the second reading on the odometer, which now displays 21,000 kilometres.

The mileage of your four-wheeler = (21,000 km - 20,000 km) /40 L

= 25 kilometres per litre.

Tips for accurate mileage calculation

To get an accurate reading of your vehicle mileage, take care of the following things-

• Use the same pump every time
• Make a note of the odometer reading immediately after refuelling
• To get the best average, use this calculation over several refuels
• For an accurate reading, drive under normal conditions instead of high traffic or uneven roads.

Why is it important to calculate your car's mileage?

Calculating your car’s mileage is necessary because it helps you understand how fuel-efficient your vehicle is. It also assists in budgeting the fuel usage for the car. Decreased mileage can indicate mechanical issues, and identifying this helps you maintain your vehicle before serious damage happens.

Good mileage ensures that your car has a good resale value if you choose to sell it.

Factors affecting car mileage

The mileage of your car is impacted by certain factors, like:

• Your driving habits: Smooth driving ensures better mileage for a longer time, and rash driving decreases the efficiency of the engine and car.
• Engine health: It depends upon timely maintenance and oil changes.
• Tyre pressure: Rightly inflated tyres ensure the well-functioning of the vehicle and offer a smooth driving experience
• The weight of the vehicle: The heaviness of the vehicle can make it harder for the engine to work. Adding excess weight to the car also reduces its mileage.
• The quality of the fuel: The purity of the fuel used in the vehicle affects the mileage and overall health of the car.
• Traffic condition: Congestion and frequent stops reduce fuel efficiency and harm

Tips for improving car mileage

You can follow a few expert tips to maintain the car mileage and improve its performance-

• Driving efficiently without sudden breaks or acceleration and maintaining a steady speed.
• Regular visits to the repair shop, timely oil changes and cleaning of the vehicle and its components are effective steps to maintain the car’s performance.
• Check the tyre pressure regularly.
• Avoid adding extra weight to the car as it reduces efficiency and mileage.
• Do not constantly use the AC at the maximum setting for prolonged periods because this can reduce mileage.

Role of car maintenance in maintaining good mileage

Car maintenance plays a big role in keeping mileage consistent. Even a well-built car can give poor mileage if not maintained properly.

• Engine oil: Old or dirty oil reduces efficiency. Regular oil changes keep the engine smooth.
• Air filter: A clogged filter restricts airflow, reducing mileage. Cleaning or replacing it improves performance.
• Spark plugs: Worn-out plugs cause incomplete fuel burning. Replacing them helps with mileage.
• Wheel alignment and balancing: Misaligned wheels cause more rolling resistance, lowering mileage.
• Regular servicing: Following the service schedule recommended for your car ensures better performance and mileage.

How mileage impacts car insurance premiums and claims

Mileage also affects your car insurance policy in the following ways:

• Low usage, low premium: If your yearly mileage is low, your insurance premium may be slightly lower because the risk of accidents is less.
• High usage, higher risk: If you drive a lot, the chances of wear and tear or accidents increase, which may impact your insurance cost.
• Claim settlement: When making claims, sometimes insurance companies may check your odometer reading to confirm the vehicle usage.

Conclusion

Calculating car mileage is simple. By knowing how much distance your car travels per litre of fuel, you can manage your budget, keep your car in good health and even plan long trips better. Mileage depends on many factors like driving habits, road conditions and maintenance. By driving smartly and keeping your car in good condition, you can improve mileage and save more in the long run.

While you take care of your car’s mileage and maintenance, don’t overlook the importance of the right insurance cover. Get expert advice on choosing the best comprehensive or third party car insurance policy for your needs by filling out the form provided on this page.

FAQs

• What is a good mileage for a car?

A mileage of around 15-20 km/l for petrol cars and 18-25 km/l for diesel cars is considered good.

• Does running the AC reduce mileage?

Yes, using the AC puts extra load on the engine and reduces mileage slightly.

• How often should I check mileage?

You don’t need to check mileage very often; once in 3-6 months or after servicing is enough.

• Can I increase my car’s mileage?

Yes. By driving smoothly, maintaining tyre pressure, servicing regularly and reducing unnecessary load, you can improve your car’s mileage.

Disclaimer: The information provided in this blog is for educational and informational purposes only. It may contain outdated data and information regarding the topic featured in the article. It is advised to verify the currency and relevance of the data and information before taking any major steps. ICICI Lombard is not liable for any inaccuracies or consequences resulting from the use of this outdated information.