Car vs. Bike Calculator
See how much money, CO2 and time a car commute costs against a bicycle commute, and how many calories you would burn switching.
🚲 What is a Car vs. Bike Comparison?
A car versus bike calculator puts the everyday choice between driving and cycling to work in plain numbers: money, carbon dioxide, time and calories. Every car trip carries a fuel cost and a tailpipe emission that scales directly with distance, while every bicycle trip carries a small maintenance cost, a real time cost, and a genuine calorie burn. None of those trade-offs are obvious from habit alone, which is exactly why putting your own commute distance, fuel price and speeds into a calculator changes the picture more than most people expect.
People reach for this comparison in a few recurring situations. Someone deciding whether to buy a second car wants to know what a bike commute would actually cost and save first. A commuter negotiating a shorter or longer distance move wants to see how sensitive the numbers are to distance. Employers running a cycle-to-work scheme want a defensible annual CO2 figure for sustainability reporting. And plenty of people simply want an honest estimate of the calories a regular commute would burn before committing to it.
The biggest misconception this calculator corrects is that cycling is free and driving's cost is only fuel. Bicycles need tyres, chains and brake pads, so this tool charges a small per-kilometre upkeep cost rather than treating cycling as free. On the other side, driving's CO2 is tied directly to fuel consumed, not to distance alone, so a thirstier car or a longer commute both push the CO2 figure up in a way that is easy to underestimate by eye.
The result is not a verdict that one mode always wins. A short, flat, low-traffic commute usually favours the bike on every measure except raw speed. A long commute on a fast road usually favours the car on time, even while it costs far more in fuel and carbon. This calculator exists to make that trade-off visible for your specific numbers, not someone else's average commute.
📐 Formula
📖 How to Use This Calculator
Steps
💡 Example Calculations
Example 1 — Typical Suburban Commute
8 km one way, 5 trips a week, 7.5 L/100km car at $1.50/L, 70 kg rider, 16 km/h bike, 30 km/h car
Example 2 — Short Urban Commute
3 km one way, 6 trips a week, 8 L/100km car at $1.20/L, 60 kg rider, 14 km/h bike, 20 km/h car
Example 3 — Long Distance Commute
15 km one way, 5 trips a week, 6 L/100km car at $1.80/L, 80 kg rider, 18 km/h bike, 50 km/h car
❓ Frequently Asked Questions
🔗 Related Calculators
How much money can you save switching from a car to a bike commute?
At 8 km one way, 5 round trips a week, a car using 7.5 L/100km at $1.50/L costs about $468 a year in fuel, against roughly $83 a year in bicycle upkeep at 2 cents per km, a saving near $385 a year. Longer commutes and thirstier cars save proportionally more.
How much CO2 does cycling instead of driving save?
All of the car's tailpipe CO2 for that trip, since cycling produces none. Using 7.5 L/100km fuel consumption and 2.31 kg CO2 per litre of petrol, an 8 km each-way commute five days a week avoids about 721 kg of CO2 a year, similar to leaving a car parked for roughly two months.
How many calories do you burn cycling to work?
Moderate cycling around 16 km/h burns about MET 8 worth of energy, which works out to roughly 8.4 kcal per kilogram of body weight per hour. A 70 kg rider doing 260 hours of commuting a year burns close to 153,000 kcal, equivalent to about 20 kg of body fat before accounting for any extra eating.
Is cycling to work actually slower than driving?
Usually, unless traffic is heavy and the distance is short. At 30 km/h average driving versus 16 km/h average cycling over an 8 km commute, driving takes about 139 hours a year against 260 hours cycling, a difference of roughly two hours a week that has to be worth it for other reasons.
What car CO2 factor should I use?
2.31 kg CO2 per litre is the standard combustion factor for petrol; diesel is closer to 2.68 kg per litre. If you know your car's official g CO2/km figure instead, you can back-calculate an equivalent fuel consumption, or simply divide that figure by 1000 and multiply by your annual distance.
Does this include the CO2 from making the bicycle?
No, this calculator only measures operating emissions, not embodied manufacturing carbon. A bicycle's production footprint is small, roughly 100 to 300 kg CO2e depending on materials, and it is typically repaid within the first few months of replacing car trips.
What is MET and why does it matter for calories burned?
MET, metabolic equivalent of task, measures how many times resting energy use a given activity requires. Moderate cycling around 16 to 19 km/h sits at about MET 8 in the Compendium of Physical Activities, which is the reference this calculator's calorie formula is built on.
How is the annual distance calculated?
One-way distance times two for a round trip, times the number of trips per week, times 52 weeks in a year. An 8 km one-way commute five days a week comes to 8 times 2 times 5 times 52, which is 4,160 km a year.
Why does bicycle maintenance cost anything at all?
Tyres wear out, chains stretch, brake pads thin down and cables corrode. A few cents per kilometre is a realistic long-run average for tyres, drivetrain parts and an occasional service, and leaving it at zero would understate the true cost of cycling.
Does the calorie estimate translate directly into weight loss?
Not reliably. The 7700 kcal-per-kilogram-of-fat conversion is a textbook energy-balance estimate that ignores appetite changes, muscle gain and metabolic adaptation. Treat the fat-loss figure as the theoretical upper bound of a consistent commute, not a promise.
How much faster does a car need to be before biking isn't worth it?
That depends entirely on what you value. This calculator reports the extra hours cycling costs each year so you can weigh it against the money and CO2 saved yourself, rather than assuming one answer fits every commuter.
What if I only cycle some days and drive the rest?
Scale the trips-per-week input down to the days you actually cycle, and every result updates to match. Two cycling days a week gives roughly two-fifths of the money, CO2 and calorie totals shown for a five-day commute.