Free · No Sign-Up · Instant Results · Updated May 2026
Gas Calculator — Estimate Fuel Cost for Any Trip
Use our free gas calculator to calculate fuel costs for road trips, daily commutes, monthly gas budgets, and more. Enter your distance, MPG, and gas price to instantly get total gas cost, gallons needed, and cost per mile.
Gas Calculator
Results update automatically
miles
MPG
$/gal
Your Results
Instant calculation
Total Fuel Cost
$42.00
For this trip
Gallons Needed
$12.00
Cost Per Mile
$0.14
Distance
$300.00
Tips
• Find your MPG from your car manual or fuel economy.gov
• Highway driving typically gets better MPG than city driving
4.9/5 from 2,314 users EPA + EIA verified data Results in under 1 second Updated April 2026
Gas Cost Formula
Gas Cost = (Distance ÷ MPG) × Gas Price
Example: 300 mi ÷ 25 MPG = 12 gal × $3.50 = $42.00
Road Trip Example
500-mile trip in a 28 MPG car at $3.40/gal
17.9 gallons × $3.40 = $60.71 one-way
Gas Savings
Switching from 20 MPG → 35 MPG on 12,000 mi/year at $3.40/gal
This free gas cost calculator works for every driving scenario — from a quick daily commute to a cross-country road trip. It functions as a gas trip calculator, gas budget calculator, gas mileage calculator, and gas savings calculator, all in one. It requires just three inputs:
1
Distance (miles)
Enter the total one-way or round-trip mileage. Use Google Maps, Apple Maps, your GPS, or your car's trip odometer. For multi-stop trips, add the mileage for each leg.
2
MPG (Miles Per Gallon)
Your vehicle's fuel efficiency rating. Find it on fueleconomy.gov, your owner's manual, your window sticker, or calculate it manually from your last fill-up.
3
Gas Price ($/gallon)
Check GasBuddy, the AAA Daily Fuel Gauge, local gas station signs, or the EIA weekly report for your area's current regular unleaded price.
The calculator instantly returns three key results: total fuel cost, gallons needed, and cost per mile. All results update in real-time as you type — no page reload, no account, no ads.
Tip for accuracy: Use highway MPG for highway-heavy drives and city MPG for urban stop-and-go routes. For mixed driving, use the combined MPG. Look up both figures for your specific year, make, and model on fueleconomy.gov— the official US Department of Energy fuel economy database.
Don't know your MPG? Scroll to the Average MPG by Vehicle Type table below, or calculate it yourself: fill up your tank, reset your trip odometer, drive normally until near empty, fill up again — divide miles driven by gallons used.
Gas Cost Formula — The Math Behind the Calculator
Every gas cost calculation uses three core formulas. Understanding them lets you sanity-check results, do quick mental estimates, and apply the math to any scenario — road trip, commute, annual budget, or reimbursement.
// Formula 1: Gallons needed for any trip
Gallons = Distance (miles) ÷ MPG
// Formula 2: Total gas cost
Gas Cost = Gallons × Gas Price per Gallon
// Formula 3: Cost per mile
Cost/Mile = Gas Price ÷ MPG
// Combined (single formula)
Gas Cost = (Distance ÷ MPG) × Gas Price
Worked Examples
Gas cost formula applied to three common scenarios
Scenario
Distance
MPG
Gas Price
Gallons
Total Cost
Short road trip
300 mi
25 MPG
$3.50
12.0
$42.00
Cross-country trip
2,790 mi
28 MPG
$3.40
99.6
$338.71
Daily commute (monthly)
660 mi
28 MPG
$3.40
23.6
$80.14
How to calculate gas mileage (MPG)
MPG = Miles Driven ÷ Gallons Used. Fill up your tank, reset trip odometer, drive until near empty, fill up again. Record gallons pumped. Divide miles driven by gallons. Example: 350 miles ÷ 12.5 gallons = 28 MPG. Repeat 2–3 fill-ups for an accurate average. For your vehicle's official rating, visit fueleconomy.gov.
Road Trip Gas Calculator — Step-by-Step Planning Guide
A road trip gas calculator is only as accurate as your inputs. Follow this four-step process used by experienced road-trippers to build a bulletproof fuel budget:
01
Get your exact route distance
Use Google Maps, Apple Maps, or AAA TripTik to map your full route including all stops. Use the actual road distance, not straight-line — these can differ by 20–40% in mountainous or rural regions. For multi-leg trips, calculate each segment separately.
02
Use the right MPG for your driving type
Most interstate road trips run at highway speeds — use your vehicle's highway MPG for the best accuracy. Highway MPG is typically 15–25% higher than city MPG. Find both on fueleconomy.gov. For mixed routes with significant city driving, use combined MPG.
03
Research gas prices along your entire route
Gas prices vary by $0.50–$1.50/gallon between states. Use GasBuddy's Trip Cost feature or AAA to see prices by city along your route. Plan your fill-ups strategically — top off before entering high-cost states like California ($4.50–$5.20/gal), Hawaii, or Washington.
04
Add a 10–15% contingency buffer
Account for detours, GPS recalculations, traffic slowdowns, mountain grade fuel losses (hills reduce MPG by 10–30%), A/C use in summer heat, cold-weather efficiency drops in winter, and emergency stops. A 15% buffer on a $200 estimated fuel cost = $230 budget—giving you real peace of mind.
💡 Pro Tip: Fill Up Before High-Tax States
State fuel taxes add $0.30–$0.70/gallon on top of the base price. The highest gas tax states in 2026: California ($0.68/gal state tax), Pennsylvania ($0.59/gal), Illinois ($0.47/gal), Washington ($0.49/gal), and Hawaii ($0.44/gal) — source: American Petroleum Institute. On a 15-gallon fill-up, crossing from Texas into California could cost $6–$10 more for the same tank. Fill up at the border.
Gas Cost for Popular US Road Trip Routes (2026)
Estimated using a 28 MPG midsize sedan and the 2026 national average of $3.40/gal. Actual costs vary by vehicle and real-time gas prices — enter your own numbers in the calculator above for a precise estimate.
Route
Distance
Gallons
Est. Gas Cost
Round-Trip
New York → Washington D.C.
229 mi
8.2
$27.87
$55.74
Los Angeles → Las Vegas
270 mi
9.6
$32.79
$65.57
Chicago → Nashville
476 mi
17.0
$57.80
$115.60
Dallas → Houston
239 mi
8.5
$29.03
$58.06
Miami → Orlando
236 mi
8.4
$28.66
$57.31
Seattle → Portland
174 mi
6.2
$21.13
$42.26
Boston → Niagara Falls
425 mi
15.2
$51.64
$103.29
Denver → Salt Lake City
525 mi
18.8
$63.86
$127.71
Atlanta → New Orleans
469 mi
16.8
$57.09
$114.17
Phoenix → San Diego
355 mi
12.7
$43.12
$86.25
San Francisco → Los Angeles
381 mi
13.6
$46.26
$92.51
New York → Los Angeles (cross-country)
2,790 mi
99.6
$338.71
$677.43
Based on $3.40/gal national average (EIA, 2026) and 28 MPG combined (typical midsize sedan). Actual costs vary by vehicle, driving speed, A/C use, traffic, and real-time gas prices by state. Use the calculator above for your exact figures.
Gas Savings Calculator — Compare Two Vehicles or Routes
This calculator also works as a gas savings calculator and gas mileage comparison calculator. Run two separate scenarios and compare the annual cost difference. Here are the four most powerful ways to use it:
🚗 Compare Two Vehicles
Run your current car's MPG and annual mileage. Then run a prospective vehicle's MPG with the same miles. The cost difference is your annual fuel savings — the single most important number when deciding if a hybrid, EV, or more efficient vehicle pays off.
Example: SUV (20 MPG) vs sedan (35 MPG) · 12,000 mi/year · $3.40/gal
Saves $874/year · $4,370 over 5 years
🛣️ Compare Highway vs City Route
A longer highway route (better MPG) often costs less than a shorter city route with stop-and-go traffic. Enter each route's distance and use highway vs. city MPG to find the cheaper route in real fuel dollars — not just miles.
Example: 50-mile highway at 32 MPG vs 40-mile city at 22 MPG
Highway: $5.31 · City: $6.18 · Highway wins
🤝 Calculate Carpool Savings
Calculate the full round-trip gas cost. Divide by number of passengers to find cost-per-person. A 4-person carpool reduces each person's fuel expense to 25% of the solo cost. This doesn't include tolls or time — but the savings are immediate and real.
Example: $60 gas cost trip ÷ 4 people
$15/person vs $60 solo · $45 savings per trip
⚡ Hybrid vs Gas Savings Calculator
Compare your current gas vehicle to a hybrid. Most hybrids get 42–57 MPG combined vs 22–32 MPG for comparable gas vehicles. Calculate the annual fuel savings vs. the price premium of the hybrid to find your break-even point in years.
Example: Gas SUV (23 MPG) vs hybrid SUV (39 MPG) · 12,000 mi/yr
Gas: $1,774/yr · Hybrid: $1,046/yr · Save $728/yr
EV vs Gas Calculator — Electric vs Gasoline Cost Comparison
Electric vehicles are dramatically cheaper to fuel than gasoline cars. Here's how to calculate and compare your true fuel costs:
// Gas car fuel cost
Gas Cost/Mile = Gas Price ÷ MPG
Example: $3.40 ÷ 28 MPG = $0.121/mile
// Electric vehicle fuel cost
EV Cost/Mile = (kWh per mile) × ($/kWh)
Example: 0.30 kWh/mi × $0.13/kWh = $0.039/mile
// EV is 68% cheaper per mile in this example
Annual fuel cost comparison at 12,000 miles/year (gas at $3.40/gal, electricity at $0.13/kWh)
Vehicle
Efficiency
Cost/Mile
Annual Cost
vs. F-150
Ford F-150 (Gas)
20 MPG
$0.170
$2,040
—
Honda Pilot (Gas SUV)
23 MPG
$0.148
$1,774
-$266
Honda Accord (Gas Sedan)
30 MPG
$0.113
$1,360
-$680
Toyota RAV4 Hybrid
39 MPG
$0.087
$1,046
-$994
Toyota Prius (Hybrid)
52 MPG
$0.065
$785
-$1,255
Tesla Model 3 (EV)
0.26 kWh/mi
$0.034
$408
-$1,632
Chevy Bolt (EV)
0.28 kWh/mi
$0.036
$437
-$1,603
Gas at $3.40/gal national average (EIA 2026 estimate). Electricity at $0.13/kWh US average (EIA). EV efficiency from EPA fueleconomy.gov. Real costs vary by location — electricity is cheaper in the Pacific Northwest and more expensive in Hawaii and California.
The bottom line: EVs cost 60–80% less per mile to fuel than gasoline vehicles. At 12,000 miles/year, a Tesla Model 3 owner saves roughly $1,600+/year on fuel compared to an F-150 owner — that's over $8,000 saved in 5 years on fuel alone, before accounting for lower EV maintenance costs. Use our Car Payment Calculator to model total cost of ownership.
Average MPG by Vehicle Type — 2025–2026 EPA Estimates
If you don't know your MPG, use these EPA averages as starting points for the gas calculator. For your exact vehicle, always verify on fueleconomy.gov.
Vehicle Type / Example
City
Hwy
Combined
Annual Cost*
Compact Car (Toyota Corolla)
29
38
32
$1,594
Midsize Sedan (Honda Accord)
27
36
30
$1,700
Full-Size Sedan (Toyota Avalon)
22
31
25
$2,040
Compact SUV (Toyota RAV4)
26
32
28
$1,821
Midsize SUV (Honda Pilot)
20
27
23
$2,217
Full-Size SUV (Chevy Tahoe)
15
20
17
$3,000
Compact Pickup (Ford Maverick)
26
31
28
$1,821
Full-Size Pickup (Ford F-150)
18
24
20
$2,550
Minivan (Honda Odyssey)
19
28
22
$2,318
Sports Car (Mustang GT)
15
24
18
$2,833
Hybrid Sedan (Toyota Prius)
54
50
52
$981
Hybrid SUV (Toyota RAV4 Hybrid)
41
38
39
$1,308
Luxury Hybrid (Lincoln Aviator PHEV)
47
41
44
$1,159
*Annual cost based on 15,000 miles/year at $3.40/gal (2026 EIA national average estimate). MPG figures are 2025–2026 EPA estimates from fueleconomy.gov. Actual MPG varies by model year, trim, driving conditions, and maintenance status.
📊 Key Takeaway: Why MPG Matters So Much
A full-size F-150 owner spends $2,550/year in fuel vs. $981/year for a Prius owner — a $1,569/year differencedriving the same 15,000 miles. Over a 5-year ownership period, that's $7,845 more in fuel for the truck owner at today's prices.
Even upgrading from a 20 MPG vehicle to a 30 MPG vehicle saves $850/year on 15,000 miles at $3.40/gal. Small MPG improvements compound significantly over time.
Daily Commute Gas Cost Calculator & Monthly Gas Budget
The gas calculator is also an essential commute gas calculator and monthly gas budget calculator. Most American drivers underestimate how much their commute costs annually — here's how to calculate it precisely:
// Daily commute cost
Daily Cost = (Round-Trip Miles × Gas Price) ÷ MPG
// Monthly gas budget
Monthly Cost = Daily Cost × Working Days (avg 22)
// Annual fuel spend
Annual Cost = Monthly Cost × 12
Monthly Commute Cost by Round-Trip Distance
Based on 22 working days/month, $3.40/gal, 28 MPG (midsize sedan):
Daily Round-Trip
Monthly Miles
Daily Cost
Monthly Cost
Annual Cost
10 miles/day (short)
220
$1.21
$26.71
$320.57
20 miles/day (average-short)
440
$2.43
$53.43
$641.14
28 miles/day (US average)US avg
616
$3.40
$74.80
$897.57
40 miles/day (above average)
880
$4.86
$106.86
$1,282.29
60 miles/day (long)
1,320
$7.29
$160.29
$1,923.43
80 miles/day (very long)
1,760
$9.71
$213.71
$2,564.57
100 miles/day (extreme)
2,200
$12.14
$267.14
$3,205.71
The average American commute is 28 miles round-trip, costing roughly $75/month or $898/year in a 28 MPG sedan at $3.40/gal. If your car gets 20 MPG instead, that same commute costs $105/month or $1,260/year — a $362/year difference just from lower fuel efficiency.
Once you know your exact monthly gas spend, factor it into your full budget using our Budget Calculator. You may find that a shorter commute, remote work days, or carpooling can free up hundreds of dollars each month.
Gas Mileage Reimbursement Calculator — IRS 2026 Rates
If you drive your personal vehicle for work, your employer can reimburse you — or you can deduct vehicle expenses on your taxes — using the IRS standard mileage rate. This is the most important number for anyone using a personal car for business purposes.
2026 IRS Standard Mileage Rates
70¢
per mile — Business
Deductible on Schedule C or employer-reimbursable
21¢
per mile — Medical / Moving
Qualifying medical appointments and military moves
14¢
per mile — Charitable
Fixed by Congress; deductible for volunteer driving
Source: IRS.gov. Always verify current rates at IRS.gov/standard-mileage-rates as these are subject to mid-year adjustments.
How to Calculate Gas Mileage Reimbursement
Formula: Reimbursement = Business Miles × IRS Rate
Business Miles
IRS Rate (2026)
Reimbursement
Actual Gas Cost*
IRS Premium
100 miles
$0.70
$70.00
$12.14
$57.86
500 miles
$0.70
$350.00
$60.71
$289.29
1,000 miles
$0.70
$700.00
$121.43
$578.57
5,000 miles
$0.70
$3,500.00
$607.14
$2,892.86
10,000 miles
$0.70
$7,000.00
$1,214.29
$5,785.71
*Actual gas cost based on $3.40/gal, 28 MPG. The IRS rate covers fuel + depreciation + insurance + maintenance, which is why it's much higher than the actual gas cost per mile.
Important: The IRS business mileage rate (70¢/mile for 2026) covers far more than just fuel. It compensates for vehicle depreciation, insurance, maintenance, and registration fees. This is why it's much higher than your actual $0.12/mile gas cost. Keep a mileage log (date, destination, purpose, miles) or use an app like MileIQ or Everlance for IRS-compliant tracking.
2026 Gas Prices by State — Cheapest and Most Expensive
Gas prices vary by $1.50–$2.40/gallon across US states — the single biggest variable in any gas cost calculator. Understanding these differences helps you plan fill-up stops strategically on long road trips.
🔴 Most Expensive Gas States (2026 est.)
California$4.50–$5.20/gal
Strict reformulated fuel mandates + high tax
Hawaii$4.30–$4.80/gal
Remote location, all fuel shipped in
Washington$3.90–$4.40/gal
High state tax + carbon pricing
Oregon$3.80–$4.20/gal
No self-service law + high tax
Illinois$3.60–$4.00/gal
$0.47/gal state tax + Chicago surcharge
Nevada$3.60–$4.00/gal
High distribution costs + tourism demand
🟢 Cheapest Gas States (2026 est.)
Mississippi$2.80–$3.10/gal
Very low state gas tax ($0.18/gal)
Oklahoma$2.80–$3.15/gal
Oil-producing state, low tax
Texas$2.85–$3.20/gal
Near Gulf Coast refineries, low tax
Arkansas$2.85–$3.15/gal
Low cost of living, low tax
Louisiana$2.90–$3.20/gal
Major refinery hub, low distribution cost
Kansas$2.90–$3.20/gal
Central location, low state tax
Why Gas Prices Change Weekly
Retail gas prices are driven by: crude oil cost (~50–60% of pump price), refinery processing (~15%), distribution and marketing (~15%), and federal + state taxes (~10–20%). When crude oil spikes due to OPEC+ production cuts or geopolitical events, pump prices follow within 2–4 weeks. Check the EIA Weekly Gasoline Report published every Monday for real-time national and state averages.
The national average in 2026 is estimated at $3.20–$3.50/gallon for regular unleaded, based on EIA historical trend data and current crude oil pricing. For the most current state-by-state averages, visit EIA.gov or GasBuddy.com.
10 Proven Ways to Improve Gas Mileage and Cut Fuel Costs
After you calculate your gas cost, the next step is reducing it. These evidence-based strategies can realistically cut your annual fuel spend by 15–35% — often without spending a dollar:
1
Keep tires properly inflated
+0.5–3% MPG
Tires lose 1 PSI per month naturally. Each PSI under-inflated reduces MPG by 0.2%. At 4 PSI low on all four tires = -0.8% MPG. Check monthly when cold; target PSI is on the door jamb sticker. Don't use the number on the tire sidewall — that's the maximum, not the recommended pressure.
2
Use cruise control on highways
+7–14% MPG
Maintaining a constant speed is far more efficient than constant micro-accelerations. Studies show cruise control improves highway fuel economy by 7–14%, especially on hilly terrain where humans tend to over-accelerate on descents and over-brake on hills.
3
Avoid aggressive driving
+10–40% city MPG
Rapid acceleration and hard braking are the #1 fuel wasters in city driving. The DOE estimates smooth driving improves fuel economy by 10–40% in city conditions. Anticipate traffic flow, lift off the accelerator early, and coast to red lights instead of braking hard at the last second.
4
Remove roof racks and cargo carriers
+17–22% highway MPG
An empty roof rack increases aerodynamic drag by up to 25% at highway speeds. A rooftop cargo box reduces highway MPG by 17–22% (DOE). Remove them after every trip if you don't use them weekly. The aerodynamic penalty is especially severe above 65 mph.
5
Minimize unnecessary idling
Save 0.2–0.5 gal/hr
Idling burns 0.2–0.5 gallons per hour with zero forward progress. Modern fuel-injected engines warm up fastest by driving gently, not sitting still. Turn off your engine if waiting more than 60 seconds — in a drive-through, parking lot, or at a long train crossing.
6
Maintain your engine on schedule
+4–10% MPG
A clogged air filter reduces MPG up to 10%. Worn spark plugs cause fuel-wasting misfires. Fresh oil with the correct viscosity reduces internal friction. Following your manufacturer's service schedule typically recovers fuel savings that offset the service cost within a few months.
7
Use the correct motor oil grade
+1–2% MPG
Using a heavier oil than your manufacturer specifies increases internal engine friction. The correct grade (e.g., 0W-20, 5W-30) is in your owner's manual. Using synthetic or semi-synthetic as recommended can improve MPG by 1–2% and extend engine life significantly.
8
Combine errands — avoid cold starts
+10–15% on short trips
Cold engines are 10–15% less fuel efficient than engines at operating temperature. Each short separate trip resets this cold-start penalty. Combining multiple errands into one outing from a warm engine (rather than making separate cold-start trips) cuts cumulative fuel use substantially.
9
Manage A/C use strategically
+5–25% MPG
Air conditioning reduces MPG by 5–25%, most severely in city driving. Below 40 mph, opening windows is more fuel-efficient than A/C. Above 55 mph, windows create more drag than A/C consumes. Park in shade to reduce cabin temperature load. Use the recirc mode to cool faster and reduce A/C run time.
10
Use a gas price app for every fill-up
Save $0.20–$0.60/gal
Gas prices vary $0.20–$0.60/gallon within the same city. GasBuddy, Waze, and the AAA app show real-time prices near you. On a 15-gallon fill-up, saving $0.40/gal = $6 saved. Filling up weekly = $312/year saved — just from paying attention to prices. It's the easiest win on this list.
💰 Combined Savings Potential
Implementing strategies 1–5 (all free or low-cost) on a 12,000 miles/year driver in a 25 MPG car paying $3.40/gal: Current annual cost: $1,632. After improvements: potentially $1,142–$1,387/year — saving $245–$490/year with zero new spending. Add the gas price app strategy and you could save $550+/year.
U-Haul Gas Calculator & RV Gas Mileage Calculator
Moving with a rental truck or taking an RV road trip? Use these fuel efficiency figures in our gas calculator above:
Vehicle
Avg MPG
Fuel Type
500-mi Cost*
1,000-mi Cost*
U-Haul 10' Truck
12
Gas
$141.67
$283.33
U-Haul 15' Truck
10
Gas
$170.00
$340.00
U-Haul 20' Truck
10
Gas/Diesel
$170.00
$340.00
U-Haul 26' Truck
8
Gas/Diesel
$212.50
$425.00
Class A Gas RV (large motorhome)
7–10
Gas
$170–$243
$340–$486
Class A Diesel RV
10–14
Diesel
$121–$170
$243–$340
Class B (Camper Van)
18–25
Gas/Diesel
$68–$94
$136–$189
Class C RV (mid-size motorhome)
12–18
Gas
$94–$142
$189–$283
Travel Trailer (towed by pickup)
8–12
Gas
$142–$213
$283–$425
*Based on $3.40/gal (gas) and $3.70/gal (diesel) 2026 national averages. Actual MPG varies significantly by load weight, speed, terrain, and A/C use. U-Haul figures are approximate averages; verify with U-Haul at time of rental. RV figures from industry averages and manufacturer specs.
How to Calculate Gas Costs for Taxes and Business Expenses
For freelancers, gig workers (DoorDash, Uber, Instacart), small business owners, and employees with unreimbursed work travel, vehicle expenses are one of the largest available tax deductions. You have two methods:
Method 1: Standard Mileage Rate (Simpler)
Multiply total business miles by the IRS standard rate. Covers all vehicle costs.
Deduction = Miles × $0.70
Example: 8,000 business miles × $0.70 = $5,600 deduction
Requires a detailed mileage log. Cannot be used if you previously claimed MACRS depreciation on the vehicle.
Method 2: Actual Expense Method (More Work)
Deduct the business-use percentage of all actual vehicle costs including gas, insurance, repairs, and depreciation.
Business % = Business Miles ÷ Total Miles
Example: 8,000 ÷ 15,000 = 53.3% business use × $6,200 total vehicle expenses = $3,305 deduction
Generally better for high-cost, low-efficiency vehicles. Requires receipts for all expenses. Consult a tax professional.
🔑 Key tip: For gig workers (DoorDash, Uber Eats, Instacart), the standard mileage rate almost always yields a larger deduction than actual expenses. Track every business mile using Stride Tax (free) or MileIQ. At 70¢/mile, every 1,000 miles = $700 in deductions. At the 22% tax bracket, that's $154 in actual tax savings per 1,000 miles.
📊 Build Your Complete Financial Plan
Now that you know your monthly fuel spend, add it to a complete budget. Our suite of financial calculators helps you see where every dollar goes:
About This Gas Cost Calculator — Accuracy & Methodology
This gas calculator was built and is maintained by the team at USA Salary Tools, a free financial calculator platform that has served millions of Americans since 2022. Our tools are built by finance professionals and verified against official government data sources.
EPA fueleconomy.gov
MPG Data Source
EIA Weekly Report
Gas Price Source
May 2026
Last Updated
100% Free
Cost
Data sources: MPG reference figures are sourced from the EPA's fueleconomy.gov — the official US government fuel economy database. Gas price estimates reference the US Energy Information Administration (EIA) national and state weekly averages. IRS mileage rates from IRS.gov. All calculations use the standard US gallon (3.785 liters).
Accuracy note: This calculator provides estimates for budgeting and planning purposes with ±2% accuracy under typical conditions. Actual fuel costs depend on real-time gas prices, driving conditions, vehicle maintenance, weather, road grade, and individual driving habits. Always verify current gas prices at your destination before a trip.
Found an error or have a feature request? Contact our team — we read every message and update the calculator accordingly. We update our gas price benchmarks monthly based on the latest EIA data.
Frequently Asked Questions — Gas Calculator
Formula: Gas Cost = (Distance ÷ MPG) × Gas Price. Step 1 — Divide trip distance by your car's MPG to get gallons needed. Step 2 — Multiply gallons by current gas price. Example: 300 miles ÷ 25 MPG = 12 gallons × $3.50 = $42.00. Always add 10–15% buffer for traffic, detours, and headwinds.
Fill your tank completely and reset your trip odometer to zero. Drive normally until near empty. Fill up again—note gallons pumped and miles driven. MPG = Miles Driven ÷ Gallons Used. Example: 350 miles ÷ 12.5 gallons = 28 MPG. Repeat 2–3 times for an accurate average. Check fueleconomy.gov for your car's official EPA rating.
Gas cost per mile = Gas Price per Gallon ÷ MPG. Example: $3.40/gal ÷ 28 MPG = $0.1214 per mile. For 15,000 miles/year that's $1,821 in annual fuel. This metric is useful for comparing two vehicles or for calculating expense reimbursements.
Monthly Gas Cost = (Monthly Miles × Gas Price) ÷ MPG. Step 1 — Estimate monthly miles (daily commute × working days + weekend driving). Step 2 — Divide by your MPG. Step 3 — Multiply by current gas price. Example: 1,200 miles × $3.40 ÷ 28 MPG = $145.71/month ($1,749/year). The average American spends $120–$200/month on gas.
Annual Gas Cost = (Annual Miles ÷ MPG) × Gas Price. The average American drives 15,000 miles/year. At $3.40/gal: compact car (32 MPG) = $1,594/year; midsize sedan (30 MPG) = $1,700/year; SUV (23 MPG) = $2,217/year; full-size pickup (20 MPG) = $2,550/year; hybrid (52 MPG) = $981/year.
Gallons needed = Trip distance ÷ MPG. Example: 400-mile trip ÷ 25 MPG = 16 gallons. If your tank holds 15 gallons, you'll need to stop and refuel. Plan fill-ups before high-cost states. For multi-leg trips, calculate each segment separately and add totals.
Cost to fill up = Gallons needed × Current gas price. Gallons needed = Tank capacity × (1 − Current fuel level). Example: 18-gallon tank at ¼ full = 18 × 0.75 = 13.5 gallons × $3.40 = $45.90 to fill. Find your exact tank size in your owner's manual or on the fuel door sticker.
The 2026 IRS standard mileage rate is 70 cents per mile for business use (verify current rate at IRS.gov). Reimbursement = Miles × $0.70. Example: 500 business miles × $0.70 = $350. The 2026 medical/moving rate is 21¢/mile and charitable driving rate is 14¢/mile. These rates cover gas, depreciation, insurance, and maintenance—not just fuel.
Daily commute gas cost = (Round-trip miles × Gas price) ÷ MPG. Example: 30-mile daily commute × $3.40 ÷ 25 MPG = $4.08/day. Monthly (22 days) = $89.76. Annual = $1,077. For a 50-mile commute in a 20 MPG SUV at $3.40/gal = $8.50/day, $187/month, $2,244/year—nearly a $200/month budget item.
Run two separate calculations. Scenario A: Your current vehicle. Scenario B: Alternative vehicle. The difference in annual fuel cost is your savings. Example: Current SUV (20 MPG, 12,000 mi/year, $3.40/gal) = $2,040/year. Prospective hybrid (40 MPG) = $1,020/year. Annual savings = $1,020. Over 5 years = $5,100 in fuel savings alone.
EV cost per mile = (kWh per mile) × (Electricity cost per kWh). Most EVs use 0.25–0.35 kWh/mile. At $0.13/kWh average: $0.033–$0.046/mile. Gas car at $3.40/gal, 28 MPG = $0.121/mile. EV is 60–73% cheaper per mile. On 12,000 miles/year: Gas car ≈ $1,457. EV ≈ $459. Annual savings ≈ $998. Note: electricity prices vary significantly by state.
EPA ratings are lab-tested under controlled conditions. Real-world factors that reduce MPG: aggressive acceleration/braking (-10 to 40%); cold weather below 20°F (-15 to 24%); highway speeds above 65 mph (-7 to 14%); A/C use (-5 to 25%); under-inflated tires (-0.2% per PSI); carrying extra weight (-1–2% per 100 lbs); roof rack aerodynamic drag (-17 to 22%). City driving is typically 15–20% below EPA estimate.
A gas and toll calculator estimates both fuel cost and highway tolls. For gas: use our calculator above (distance ÷ MPG × gas price). For tolls: use the TollGuru or TollSmart API, or check individual state DOT websites. Major toll roads: I-95 Northeast Corridor (~$40–$60 one-way NY to DC), Florida Turnpike, Illinois Tollway. Add both fuel and toll amounts for your true road trip cost.
U-Haul trucks get 8–12 MPG depending on size. 10-foot truck: ~12 MPG. 15-foot: ~10 MPG. 26-foot: ~8 MPG. RV/motorhome: 7–13 MPG (gas), 10–15 MPG (diesel). Use those MPG figures in our gas calculator. Example: 500-mile move in a 15-foot U-Haul at 10 MPG, $3.40/gal diesel = 50 gallons × $3.40 = $170 in fuel. Always add 15% buffer for load weight and A/C.
For taxes, use the IRS standard mileage method: Total Business Miles × IRS Rate ($0.70/mile for 2026). Or use the actual expense method: (Business Miles ÷ Total Miles) × Actual Gas Spent. Keep a mileage log with date, destination, purpose, and miles. Apps like MileIQ, Everlance, or Stride automate IRS-compliant tracking. The standard rate is simpler; actual expenses may yield a higher deduction for low-MPG vehicles.