Drive vs Fly Cost Calculator

Understanding the Drive vs Fly decision

Choosing between driving and flying for a trip is a common dilemma. The headline price (gas vs airfare) is rarely the whole story. This calculator helps you estimate the total out-of-pocket cost for each option and, if you choose, the time cost based on your personal value of time. That way, the comparison reflects not only what you pay, but also what you give up in hours spent traveling.

The goal is not to declare one mode “better” in all situations, but to show the tradeoffs clearly: flying often saves time but adds fixed per-person costs; driving spreads costs across travelers but can take many more hours—especially for longer distances or slower routes.

What the calculator includes

Driving

• Fuel cost based on distance, MPG, and gas price.
• Other driving cost per mile (optional) for tolls, wear-and-tear, maintenance allowance, and depreciation-style per-mile estimates.
• Time cost (optional) based on distance, your average driving speed, and your value of time per hour.

Flying

• Ticket cost per person multiplied by the number of travelers.
• Time cost (optional) based on total flight time “door-to-door” (including security/boarding) and your value of time. This is multiplied by the number of travelers to reflect total time across the group.

Formulas used

These are the core equations behind the calculator.

Driving cost

Where:

• D = trip distance (miles)
• MPG = vehicle fuel efficiency (miles per gallon)
• P = gas price per gallon
• C_mile = other driving cost per mile (tolls/wear/etc.)
• T_drive = driving time (hours) = D / speed
• V_time = value of time per hour (optional; set to 0 if blank)

Flying cost

C_fly = (F × N) + (T_fly × V_time × N)

• F = flight ticket price per person
• N = number of travelers
• T_fly = total flight time including airport time (hours)

Interpreting the results

After you enter your numbers, compare the totals:

• Driving total will increase most with distance and with low MPG/high gas prices. Adding a realistic per-mile “other cost” often changes the result more than people expect on long drives.
• Flying total increases mainly with the number of travelers and the ticket price. For solo travelers, flying can become cheaper at shorter distances than it would for a family.
• Value of time can flip the decision: if time is highly valuable (or if you strongly prefer not to spend long hours traveling), flying may be “cheaper” in total cost even if the cash price is higher.

Also consider what “cheaper” means for you: the calculator can reflect cash cost only (leave value of time blank) or cash + time (enter a value of time).

Worked example

Suppose two travelers are planning a 600-mile trip:

• Distance: 600 miles
• Car efficiency: 30 mpg
• Gas price: $3.80/gal
• Other driving cost: $0.07/mile
• Average driving speed: 60 mph (so driving time ≈ 10 hours)
• Flight ticket: $180/person (2 travelers)
• Total flight time incl. airport: 5 hours
• Value of time: $20/hour

Driving fuel cost = (600 / 30) × 3.80 = 20 × 3.80 = $76. Other driving cost = 600 × 0.07 = $42. Time cost = 10 × 20 = $200. Driving total ≈ $318.

Flying ticket cost = 180 × 2 = $360. Time cost = 5 × 20 × 2 = $200. Flying total ≈ $560.

In this scenario, driving is cheaper even after valuing time. But if tickets drop, the group size changes, or you increase your value-of-time, the result can switch quickly.

Assumptions & limitations

• One-way vs round-trip: Inputs are treated as entered. If your distance is one-way but you’re planning a round-trip, double the distance (and consider doubling flight cost as well if you’re pricing a round-trip fare).
• Flight time is “door-to-door”: The most realistic comparison uses total time including getting to the airport, security, boarding, layover buffers, and ground travel on arrival. If you enter only airborne time, flying may look artificially favorable.
• Not all flight fees are included: Baggage fees, seat fees, parking at the airport, rideshares, and incidental costs can be substantial and vary widely.
• Driving costs vary by vehicle and route: The “other cost per mile” is a simplification. Mountain routes, heavy traffic, tire wear, and toll-heavy corridors can change costs meaningfully.
• Speed is an average: Stops, traffic, weather, and construction can reduce true average speed below what you expect.
• Time value is personal: The calculator treats time as a linear dollar value. In reality, fatigue, stress, enjoyment of a road trip, and the ability to work while traveling can change the effective value of time.

FAQ

Should I include the value of time?

If you want a pure out-of-pocket comparison, leave it blank. If you want a “total cost” view, enter a value that represents what an hour of travel time is worth to you (or your group).

What should I use for “other driving cost per mile”?

Use 0 if you only want fuel. Otherwise, include estimated tolls and a wear/maintenance allowance (many drivers use a small per-mile figure). The right value depends on your car, tires, maintenance schedule, and route.

Is the flight time per person?

The entered flight time is per traveler, and the calculator multiplies the time cost by the number of travelers so group time is reflected consistently (similar to multiplying ticket cost by travelers).

How do I handle a return trip?

Either enter the full round-trip distance and the round-trip ticket price, or double your one-way results—just be consistent across both modes.