Mileage Calculator
(Gas, Fuel & Reimbursement)

To calculate fuel mileage, divide the distance traveled by the amount of fuel used. For example, if you drove 300 miles and used 10 gallons of gas, your fuel mileage is 30 MPG (300 ÷ 10 = 30). For the most accurate results, fill your tank completely, record your odometer reading, drive normally, refill the tank, and then divide the miles driven by the gallons added.

Calculate gas mileage by dividing miles driven by gallons of gas used. The step-by-step process: (1) Fill your tank completely, (2) Record odometer reading, (3) Drive normally until you need to refuel, (4) Fill tank again and note gallons added, (5) Record new odometer reading, (6) Subtract starting mileage from ending mileage, (7) Divide miles driven by gallons used. This gives you your MPG (miles per gallon).

Multiply the total miles driven for business purposes by the current mileage rate. For example, if you drove 100 miles at a rate of $0.67 per mile, your reimbursement would be $67 (100 × $0.67 = $67). The IRS standard mileage rate for 2025 is $0.70 per mile for business use. Always keep detailed records including dates, destinations, and purposes of trips.

Track all business-related driving miles throughout the year using a mileage log or tracking app. Record the date, starting location, destination, purpose, and miles driven for each trip. At tax time, multiply your total business miles by the IRS standard mileage rate for that tax year. For 2025, the rate is $0.70 per mile. Keep detailed records for at least 3 years in case of an audit.

The IRS standard mileage rate for 2025 is 70 cents per mile for business use. This rate is updated annually and covers gas, maintenance, insurance, and depreciation. Many employers use this rate or a similar amount for mileage reimbursement. The rate is considered fair because it reflects the actual cost of operating a vehicle based on annual studies of fixed and variable costs.

MPG (miles per gallon) is used primarily in the United States and measures how many miles you can drive on one gallon of fuel. KPL (kilometers per liter) is used in countries with the metric system and measures how many kilometers you can drive on one liter of fuel. To convert: 1 MPG = 0.425 KPL, or 1 KPL = 2.35 MPG.

Calculate your gas mileage every 2-3 fill-ups to track your vehicle's fuel efficiency over time. Regular monitoring helps you identify issues like decreased efficiency (which may indicate maintenance needs), understand how driving habits affect fuel consumption, and budget accurately for fuel costs. Seasonal variations are normal, so track over several months for the best average.

You can deduct either mileage OR actual expenses (including gas), but not both. The standard mileage deduction is usually simpler and often more beneficial. It covers gas, maintenance, insurance, and depreciation in one rate. If you choose actual expenses, you must track all vehicle costs and can only deduct the business-use percentage. Consult a tax professional to determine which method is best for your situation.

Multiple factors affect gas mileage: driving habits (aggressive acceleration/braking reduces MPG by 15-30%), vehicle maintenance (under-inflated tires reduce MPG by 0.2% per PSI drop), speed (MPG decreases significantly above 50 mph), vehicle load (extra 100 lbs reduces MPG by 1%), weather conditions (cold weather and headwinds reduce efficiency), and terrain (hills and mountains decrease MPG).

Our mileage calculator provides accurate results based on the data you input. For gas mileage calculations, accuracy depends on precise measurements of distance and fuel used. For reimbursement calculations, we use current standard rates. For distance-based mileage, results are estimates - use our Distance Calculator for exact driving distances. Always verify important calculations and consult professionals for tax or legal matters.

Keep a detailed mileage log recording: date of trip, starting location, destination, business purpose, odometer readings (start and end), and total miles. Use a dedicated mileage tracking app, spreadsheet, or paper log. Record trips immediately to avoid forgetting details. Separate business miles from personal miles. Include supporting documentation like meeting confirmations or client invoices. The IRS requires contemporaneous records.

Good gas mileage varies by vehicle type. Compact cars: 30-40 MPG is good, 40+ MPG is excellent. Midsize sedans: 25-35 MPG is good. SUVs: 20-28 MPG is good. Trucks: 18-25 MPG is good. Hybrids: 40-60 MPG is typical. Electric vehicles measure efficiency differently (MPGe). Compare your vehicle's actual MPG to its EPA-estimated MPG to gauge performance.