Miles per Gallon (UK) to Miles per Gallon (US) Converter
Convert miles per UK gallon to miles per US gallon with our free online fuel consumption converter.
Quick Answer
1 Miles per Gallon (UK) = 0.832674 miles per US gallon
Formula: Miles per Gallon (UK) × conversion factor = Miles per Gallon (US)
Use the calculator below for instant, accurate conversions.
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Miles per Gallon (UK) to Miles per Gallon (US) Calculator
How to Use the Miles per Gallon (UK) to Miles per Gallon (US) Calculator:
- Enter the value you want to convert in the 'From' field (Miles per Gallon (UK)).
- The converted value in Miles per Gallon (US) will appear automatically in the 'To' field.
- Use the dropdown menus to select different units within the Fuel Consumption category.
- Click the swap button (⇌) to reverse the conversion direction.
How to Convert Miles per Gallon (UK) to Miles per Gallon (US): Step-by-Step Guide
Converting Miles per Gallon (UK) to Miles per Gallon (US) involves multiplying the value by a specific conversion factor, as shown in the formula below.
Formula:
Conversion factor not available for this pair.Example Calculation:
Example calculation not available for Miles per Gallon (UK) to Miles per Gallon (US).
Disclaimer: For Reference Only
These conversion results are provided for informational purposes only. While we strive for accuracy, we make no guarantees regarding the precision of these results, especially for conversions involving extremely large or small numbers which may be subject to the inherent limitations of standard computer floating-point arithmetic.
Not for professional use. Results should be verified before use in any critical application. View our Terms of Service for more information.
Need to convert to other fuel consumption units?
View all Fuel Consumption conversions →What is a Miles per Gallon (UK) and a Miles per Gallon (US)?
Miles per Gallon (UK) is a unit of fuel economy expressing the distance in statute miles traveled per Imperial gallon of fuel.
Formula: MPG (UK) = Miles Driven ÷ Imperial Gallons Used
The Imperial Gallon: The Imperial gallon is exactly 4.54609 liters.
- It is about 1.2 times larger than the US liquid gallon.
- 1 Imperial Gallon ≈ 1.201 US Gallons.
Why this matters: If you read a US car review saying a car gets "30 MPG," that sounds low to a British driver. In UK units, that same efficiency would be "36 MPG."
Miles per Gallon (US) is a unit of fuel economy that expresses the distance in statute miles that a vehicle can travel using one US liquid gallon of fuel.
Formula: MPG = Miles Driven ÷ Gallons Used
Mathematical relationship:
- 1 US MPG = 0.425144 kilometers per liter (km/L)
- 1 US MPG = 1.20095 UK MPG (Imperial gallon)
- To convert MPG to L/100km: L/100km = 235.215 ÷ MPG
- To convert L/100km to MPG: MPG = 235.215 ÷ L/100km
The US Gallon vs. Imperial Gallon
Critical distinction for international comparisons:
US Gallon (US liquid gallon):
- Exactly 231 cubic inches by legal definition
- 3.785411784 liters (exactly)
- 128 US fluid ounces
- Standard for fuel sales in the United States
Imperial Gallon (UK gallon):
- 4.54609 liters (exactly)
- 160 Imperial fluid ounces
- About 20% larger than US gallon
- Used in United Kingdom, Canada (though Canada increasingly uses liters)
Conversion:
- 1 US gallon = 0.832674 Imperial gallons
- 1 Imperial gallon = 1.20095 US gallons
Real-world impact:
- A car rated 30 US MPG = 36 UK MPG (same efficiency, different gallon size)
- A car rated 50 UK MPG = 41.6 US MPG
- Always check which gallon is being referenced when comparing international fuel economy figures
MPG vs. L/100km: Opposite Logic
Two different ways to measure the same thing:
MPG (Miles Per Gallon) — "Fuel Economy":
- Measures distance per fuel unit (output/input)
- Higher numbers = better efficiency
- Logic: "How far can I go on this fuel?"
- Used in: United States
L/100km (Liters Per 100 Kilometers) — "Fuel Consumption":
- Measures fuel per distance unit (input/output)
- Lower numbers = better efficiency
- Logic: "How much fuel do I need to go 100 km?"
- Used in: Europe, Australia, Canada, most of the world
Conversion relationship is non-linear:
- 10 MPG = 23.5 L/100km (poor efficiency)
- 20 MPG = 11.8 L/100km (mediocre)
- 30 MPG = 7.8 L/100km (good)
- 40 MPG = 5.9 L/100km (very good)
- 50 MPG = 4.7 L/100km (excellent/hybrid)
Why L/100km is mathematically superior: It's linear with fuel consumption. Doubling L/100km doubles fuel usage. But doubling MPG does NOT halve fuel usage (see "MPG Illusion" in conversion mistakes).
Note: The Miles per Gallon (UK) is part of the imperial/US customary system, primarily used in the US, UK, and Canada for everyday measurements. The Miles per Gallon (US) belongs to the imperial/US customary system.
History of the Miles per Gallon (UK) and Miles per Gallon (US)
1824: The Imperial Standard
Before 1824, there were different gallons for wine, ale, and corn. The British Weights and Measures Act of 1824 swept them all away and created one "Imperial Gallon" based on the volume of 10 pounds of water. This standard spread across the British Empire.
The Metric Mix
The UK began metricating in the 1960s and 70s.
- Roads: Distances stayed in miles.
- Fuel Pumps: Switched to liters in the 1980s.
- Cars: Continued to measure efficiency in MPG. This created a unique British hybrid system: you buy fuel in liters, drive in miles, and calculate economy in miles per gallon.
Modern Regulations
Today, official UK fuel economy figures (WLTP test cycle) are published in both L/100km (metric) and MPG (Imperial). However, virtually all marketing and consumer discussions focus on the MPG figure.
The Gas Guzzler Era (1950s-1973)
When efficiency didn't matter:
Post-WWII American automotive culture:
- Cheap gasoline: 30-36 cents per gallon (equivalent to ~$2-3 in 2024 dollars)
- Big engines: V8 engines standard in full-size sedans, muscle cars with 400+ cubic inch displacement
- Low efficiency: Typical family sedan: 8-12 MPG, luxury cars/sports cars: 6-10 MPG
- No pressure to improve: Fuel economy rarely advertised, not a selling point
Typical fuel economy (early 1970s):
- 1971 Cadillac Eldorado: 8 MPG city, 11 MPG highway
- 1970 Ford Mustang Boss 429: 6-8 MPG
- 1972 Chevrolet Impala: 10 MPG city, 14 MPG highway
- Compact cars (Volkswagen Beetle, Toyota Corolla): 25-30 MPG (considered "economy" cars, not mainstream)
1973 Oil Crisis: The Catalyst
When everything changed overnight:
October 1973: OPEC oil embargo:
- Background: Arab oil-producing nations embargoed oil exports to the US over support for Israel in Yom Kippur War
- Immediate impact: Gas prices quadrupled from ~38 cents to $1.50+ per gallon
- Supply shortages: Long lines at gas stations, odd-even day rationing by license plate
- Public panic: Americans suddenly concerned about fuel efficiency for the first time
Economic impact:
- $50 fill-up shock: What cost $5 to fill now cost $20-25
- Recession: High energy prices contributed to 1973-1975 recession
- Demand shift: Consumers suddenly wanted smaller, more efficient cars—but American automakers had none ready
Import invasion:
- Japanese manufacturers (Toyota, Honda, Datsun) gained massive market share with fuel-efficient compacts
- Volkswagen Beetle sales surged
- American "Big Three" (GM, Ford, Chrysler) caught flat-footed with only gas guzzlers in production
1975: Corporate Average Fuel Economy (CAFE) Standards
Government mandates efficiency:
Energy Policy and Conservation Act (1975):
- Passed by Congress to reduce US petroleum dependence
- Created CAFE standards requiring automakers to meet fleet-wide average MPG targets
- Separate standards for passenger cars and light trucks
CAFE targets evolution:
- 1978 (first year): 18.0 MPG passenger cars
- 1985: 27.5 MPG passenger cars (53% increase!)
- 1990-2010: Standards largely stagnant at 27.5 MPG (lobbying pressure)
- 2011-2025: Rapid increases toward 50+ MPG equivalent (under Obama administration)
- 2025 target: ~50 MPG equivalent fleet average (includes credits for EVs)
How CAFE works:
- Automakers must achieve fleet-wide average (not every individual vehicle)
- Selling one 50 MPG hybrid allows selling one 25 MPG SUV to maintain 37.5 MPG average
- Gas Guzzler Tax (1978): $1,000-$7,700 penalty for cars under 22.5 MPG combined
- Light trucks (SUVs, pickups) have lower standards, creating "SUV loophole"
Impact:
- American automotive revolution: Forced development of fuel injection, overdrive transmissions, aerodynamics, weight reduction
- Average new car MPG doubled from 13-14 MPG (1975) to 27+ MPG (1985)
- Controversial: Automakers claimed standards were impossible, but achieved them
1978: EPA Fuel Economy Testing
Standardizing MPG measurements:
EPA Federal Test Procedure (FTP):
- Created standardized lab tests to ensure comparable ratings across all vehicles
- Original tests (1978-2007): Only City and Highway cycles
- 2008 revision: Added high-speed, air conditioning, and cold-temperature tests for real-world accuracy
Three standard ratings:
- City MPG: EPA FTP-75 urban driving cycle (stop-and-go, avg 21 mph, 11 miles, 31 minutes)
- Highway MPG: EPA Highway Fuel Economy Test (steady speeds 48-60 mph, 10 miles, 12.5 minutes)
- Combined MPG: Weighted average (55% city, 45% highway)
Why 2008 revision was needed:
- Pre-2008 EPA ratings often 15-30% higher than real-world experience
- Didn't account for A/C use, aggressive acceleration, high speeds (70+ mph)
- Post-2008 ratings reduced by ~10-20% across the board for accuracy
The Monroney Sticker (1975-Present)
Making MPG visible to consumers:
Automobile Information Disclosure Act:
- Mandated fuel economy label on every new car window sticker
- Named after Senator Mike Monroney (Oklahoma)
Modern EPA sticker includes:
- City/Highway/Combined MPG in large numbers
- Estimated annual fuel cost ($1,750, $2,100, etc.)
- Fuel cost savings/penalty vs. average new car (+$500 or -$1,200)
- Fuel consumption bar graph (gallons per 100 miles)
- 10-year fuel cost estimate
- Comparison to vehicles in same class
Psychological impact: MPG became a primary car-buying criterion alongside price, safety, reliability.
Modern Era (2010s-Present)
Evolution beyond traditional MPG:
2011: MPGe (Miles Per Gallon equivalent) for EVs:
- Electric vehicles don't use gallons, so EPA created MPGe
- Definition: Distance traveled on electrical energy equivalent to 1 gallon of gasoline (33.7 kWh)
- Example: Tesla Model 3 rated 130 MPGe (travels 130 miles on 33.7 kWh of electricity)
Hybrid proliferation:
- 2000-2010: Toyota Prius establishes hybrid as viable (45-50 MPG)
- 2010s: Every major automaker offers hybrid options
- Modern hybrids: Routine 50-60 MPG combined ratings
Turbocharged downsizing:
- Smaller engines (1.5L-2.0L turbo) replace larger V6s/V8s
- Maintain power but improve efficiency (25-30 MPG in midsize sedans vs. 18-22 MPG previously)
Consumer dashboard displays:
- Real-time instantaneous MPG gauges standard on most vehicles
- Trip computer tracks average MPG over tank/trip
- Some show "driving score" encouraging efficient habits
Common Uses and Applications: miles per UK gallon vs miles per US gallon
Explore the typical applications for both Miles per Gallon (UK) (imperial/US) and Miles per Gallon (US) (imperial/US) to understand their common contexts.
Common Uses for miles per UK gallon
Car Dashboards
Almost every car sold in the UK, even from German or Japanese manufacturers, defaults to displaying MPG (UK) on the trip computer.
Advertising
"Up to 65 MPG!" is a standard headline in British car ads. Manufacturers know that L/100km (e.g., "4.3 L/100km") is not intuitive for most British buyers.
Used Car Market
When buying a second-hand car, the first question is often "What's the MPG?" It is the primary metric for affordability.
When to Use miles per US gallon
EPA Fuel Economy Ratings
Every car sold in the US has three official MPG ratings:
1. City MPG:
- Test: EPA Urban Dynamometer Driving Schedule (UDDS/FTP-75)
- Simulates: Stop-and-go urban traffic
- Parameters: 11.04 miles, 31.2 minutes, average 21.2 mph, max 56.7 mph
- 23 stops, frequent acceleration/deceleration
- Typically lowest MPG (except hybrids with regenerative braking)
2. Highway MPG:
- Test: EPA Highway Fuel Economy Test (HWFET)
- Simulates: Free-flowing highway cruising
- Parameters: 10.26 miles, 12.75 minutes, average 48.3 mph, max 60 mph
- No stops, steady speeds
- Typically highest MPG (less braking, consistent engine load)
3. Combined MPG:
- Weighted average: 55% city, 45% highway
- Most representative of mixed driving
- Used for CAFE compliance
Additional tests (added 2008):
- High Speed Test: 80 mph bursts, aggressive acceleration
- Air Conditioning Test: 95°F ambient, A/C at max
- Cold Temperature Test: 20°F ambient, cold engine start
Consumer Car Shopping
MPG as a primary buying criterion:
Typical consumer priorities (2024):
- Price (54% top factor)
- Fuel economy (48% top factor)
- Safety (47%)
- Reliability (45%)
- Comfort/features (38%)
Price sensitivity:
- $4+ per gallon: Fuel economy becomes #1 priority for most buyers
- $2-3 per gallon: Balanced consideration
- Under $2 per gallon: Fuel economy deprioritized (shift to SUVs/trucks)
Search behavior:
- 78% of car buyers research fuel economy before dealership visit
- Online tools: EPA fueleconomy.gov, manufacturer comparison tools
- Dealers emphasize monthly fuel savings in pitch ("Save $100/month vs. your current vehicle")
Environmental Impact and CO2 Emissions
MPG directly correlates to greenhouse gas emissions:
Chemistry of gasoline combustion:
- Burning 1 gallon of gasoline produces 19.6 pounds (8.9 kg) of CO2
- Each gallon also produces ~2 pounds of water vapor + trace emissions
Emissions by MPG rating (15,000 miles/year):
- 15 MPG vehicle: 1,000 gallons = 19,600 lbs CO2 = 9.8 tons CO2/year
- 30 MPG vehicle: 500 gallons = 9,800 lbs CO2 = 4.9 tons CO2/year
- 50 MPG hybrid: 300 gallons = 5,880 lbs CO2 = 2.9 tons CO2/year
Context:
- Average American: ~16 tons CO2/year total (all sources)
- Transportation sector: ~29% of US greenhouse gas emissions
- Personal vehicles: ~60% of transportation emissions
Improving from 20 MPG to 40 MPG:
- Reduces CO2 by 50% (7,350 lbs/year reduction for 15,000 miles)
- Equivalent to: Planting ~340 tree seedlings (10-year growth)
Fuel Budget Planning
Monthly and annual fuel cost estimation:
Online calculators:
- EPA fueleconomy.gov: Personalized cost calculator (enter annual miles, local gas price, vehicle)
- Manufacturer websites: Fuel cost comparison tools
- GasBuddy: Local price tracking + MPG cost estimator
Employer reimbursement:
- IRS standard mileage rate (2024): 67 cents/mile (includes fuel + maintenance + depreciation)
- Fuel-only cost: Varies by MPG and gas price (20 MPG at $3.50/gal = 17.5 cents/mile for fuel alone)
Fleet management:
- Commercial fleets prioritize high-MPG vehicles to reduce operating costs
- Delivery companies (UPS, FedEx, Amazon) invest heavily in efficient vehicles/route optimization
- Example: 100-vehicle fleet @ 20,000 miles/year each, upgrading from 15 MPG to 20 MPG saves $233,333/year (at $3.50/gal)
"Gas Guzzler Tax" Avoidance
Federal penalty for low-efficiency cars:
Energy Tax Act of 1978:
- Excise tax on new cars below 22.5 MPG combined (unadjusted EPA rating)
- Does NOT apply to trucks, SUVs, minivans (10,000+ GVWR exempt)
- Penalty ranges from $1,000 to $7,700 based on severity
2024 Gas Guzzler Tax rates:
- 22.5 MPG: $0
- 21.5-22.4 MPG: $1,000
- 20.5-21.4 MPG: $1,300
- 19.5-20.4 MPG: $1,700
- 18.5-19.4 MPG: $2,100
- 17.5-18.4 MPG: $2,600
- 16.5-17.4 MPG: $3,000
- 15.5-16.4 MPG: $3,700
- 14.5-15.4 MPG: $4,500
- 13.5-14.4 MPG: $5,400
- 12.5-13.4 MPG: $6,400
- Under 12.5 MPG: $7,700
Affected vehicles:
- High-performance sports cars (Dodge Challenger SRT Hellcat, Lamborghini, Ferrari)
- Luxury sedans with large engines (some BMW M, Mercedes AMG models)
- Not affected: SUVs and trucks (even if they get worse MPG) due to "light truck" exemption
Additional Unit Information
About Miles per Gallon (US) (MPG (US))
What is a "good" MPG?
2024 standards for "good" fuel economy:
- Under 20 MPG: Poor efficiency (large trucks, SUVs, sports cars, older vehicles)
- 20-25 MPG: Below average (many SUVs, some trucks, V6/V8 sedans)
- 25-30 MPG: Average for new vehicles (typical midsize sedan, efficient SUV)
- 30-40 MPG: Good/above average (compact cars, efficient sedans, diesel vehicles)
- 40-50 MPG: Excellent (hybrids, most efficient gas cars)
- 50+ MPG: Outstanding (dedicated hybrids like Prius, Ioniq)
Context matters: A 20 MPG pickup truck might be excellent for trucks, but poor for a sedan.
How do I calculate my real MPG?
The most accurate method (hand calculation at fuel pump):
- Fill tank completely: Pump until automatic shutoff clicks
- Reset trip odometer to zero
- Drive normally until tank is 1/4 to 1/8 full (more miles = more accurate)
- Fill tank again completely until automatic shutoff clicks
- Record: Gallons added (from pump display), miles driven (from trip odometer)
- Calculate: Miles driven ÷ Gallons used = MPG
Example:
- Trip odometer: 347 miles
- Fuel pump: 12.4 gallons
- MPG = 347 ÷ 12.4 = 28.0 MPG
Accuracy tips:
- Use the same gas station/pump if possible (different pump angles affect "full")
- Multiple fill-ups averaged together more accurate than single calculation
- Don't rely solely on dashboard MPG display (often 3-10% optimistic)
Does driving faster lower MPG?
Yes, significantly. Speed kills efficiency.
Why:
- Aerodynamic drag increases with the square of speed: Doubling speed = 4× drag force
- At highway speeds, 50-70% of engine power fights air resistance
- Faster speeds also reduce engine efficiency (RPM-dependent)
Real-world impact:
- 55 mph: Optimal efficiency for most vehicles (baseline)
- 65 mph: ~10-15% worse MPG than 55 mph
- 75 mph: ~20-25% worse MPG than 55 mph
- 85 mph: ~30-35% worse MPG than 55 mph
Example (2020 Honda Accord):
- 60 mph: 42 MPG
- 70 mph: 36 MPG (14% reduction)
- 80 mph: 31 MPG (26% reduction)
Sweet spot: Most vehicles achieve maximum MPG between 45-60 mph (typically 55 mph peak).
What is MPGe?
MPGe = Miles Per Gallon equivalent (for electric vehicles)
The problem: EVs don't use gallons of gasoline, so traditional MPG doesn't apply.
EPA solution: Convert electricity consumption to gasoline-equivalent energy:
- Definition: Distance traveled using electrical energy equivalent to 1 gallon of gasoline
- Energy equivalency: 33.7 kWh of electricity = energy in 1 gallon of gasoline
Calculation:
- EV uses 30 kWh to travel 100 miles
- 100 miles ÷ (30 kWh ÷ 33.7 kWh/gal) = 112 MPGe
Examples:
- Tesla Model 3: ~130 MPGe combined
- Chevrolet Bolt EV: ~120 MPGe combined
- Ford F-150 Lightning: ~70 MPGe combined (heavier truck)
What it means: An EV rated 120 MPGe is "equivalent" to a gas car getting 120 MPG in terms of energy efficiency.
Cost comparison: Electricity typically cheaper than gasoline per mile (even with 3-4× "efficiency")
Why is City MPG usually lower than Highway MPG?
City driving is inherently less efficient due to constant acceleration and braking:
Energy loss mechanisms:
- Frequent acceleration from stops: Takes significant energy to overcome inertia
- Braking wastes energy: Kinetic energy converted to heat (wasted) every stop
- Idling at red lights: 0 MPG while stopped (engine running, no miles)
- Lower average speeds: Engine operates less efficiently at low RPM/load
- More accessories: A/C, lights, electrical draw impacts efficiency more at low speeds
Highway advantages:
- Steady speed: Minimal acceleration/braking, constant engine load
- Optimal RPM: Modern cars efficient at ~1,500-2,500 RPM (typical 60-70 mph cruising)
- Momentum maintenance: No energy wasted on stops
- Overdrive gear: Engine RPM minimized for cruising
Exception — Hybrids: Often better City MPG than Highway because:
- Regenerative braking recaptures energy normally wasted
- Electric-only operation at low speeds (engine off)
- Engine shuts off at stops (zero fuel consumption idling)
- Example: 2024 Toyota Prius: 57 city / 56 highway / 56 combined (city slightly better!)
How much does AC use affect MPG?
Air conditioning can reduce MPG by 5-25% depending on conditions.
Impact factors:
- Outside temperature: Hotter = more A/C work = more fuel penalty
- Driving type: City (stop-and-go) affected more than highway
- A/C setting: Max cold + high fan uses most, eco mode uses less
- Vehicle size: Small engines feel bigger percentage impact
Real-world examples:
- 95°F+ day, city driving, max A/C: 20-25% MPG reduction
- 85°F day, highway cruising, moderate A/C: 5-10% MPG reduction
- Mild day, eco A/C mode: 3-5% MPG reduction
Windows down vs. A/C:
- City driving (<40 mph): Windows down saves fuel
- Highway (>50 mph): A/C more efficient than windows down (aerodynamic drag penalty exceeds A/C consumption)
Heat in winter: Uses waste engine heat, minimal fuel penalty (~1-2% from increased electrical load for blower fan only).
Do diesel vehicles get better MPG than gasoline?
Yes, diesel engines are 20-40% more fuel efficient than comparable gasoline engines.
Why diesels are efficient:
- Higher compression ratio: 16:1-20:1 (diesel) vs. 10:1-12:1 (gas) = more energy extracted
- Higher energy density: Diesel fuel contains ~10-15% more energy per gallon
- Lean combustion: Excess air (no throttle) reduces pumping losses
- Lower RPM operation: Diesel torque curve allows cruising at 1,500-2,000 RPM
Typical MPG advantage:
- Gasoline midsize sedan: 30 MPG combined
- Diesel midsize sedan: 40 MPG combined (33% better)
- Gasoline pickup truck: 20 MPG combined
- Diesel pickup truck: 26 MPG combined (30% better)
Examples:
- Chevrolet Silverado 3.0L diesel: 26 MPG combined vs. 20 MPG (5.3L gas)
- BMW 328d (diesel, discontinued): 37 MPG vs. 28 MPG (328i gas)
- Volkswagen Jetta TDI: 39 MPG vs. 33 MPG (1.4T gas)
Tradeoffs:
- Higher purchase price: $2,000-$5,000 diesel premium
- More expensive fuel: $0.30-$0.50/gal more than regular gas (varies)
- Emissions systems complexity: DEF (diesel exhaust fluid) maintenance
What is the most fuel-efficient gas-only car?
2024 most efficient non-hybrid gas vehicles (US market):
- Mitsubishi Mirage: 39 MPG combined (36 city/43 highway)
- Nissan Versa: 35 MPG combined (32 city/40 highway)
- Hyundai Elantra (base 2.0L): 37 MPG combined (33 city/43 highway)
- Honda Civic (base): 36 MPG combined (33 city/42 highway)
- Toyota Corolla: 35 MPG combined (32 city/41 highway)
Historical context: Modern efficient gas cars (35-40 MPG) approach 1990s Honda Civic CRX HF (50 MPG), but with more safety, emissions control, and features.
If hybrids included: Toyota Prius (57 MPG) and Hyundai Ioniq Hybrid (59 MPG) are most efficient non-plug-in vehicles.
Does premium gas improve MPG?
It depends on the vehicle:
Vehicles REQUIRING premium (91-93 octane):
- Using regular (87 octane) causes ECU to retard timing
- Result: 3-8% MPG reduction + slight power loss
- Examples: Most luxury/performance cars (BMW M, Mercedes AMG, Porsche, Nissan GT-R)
Vehicles RECOMMENDING premium (but regular okay):
- Optimized for premium but can adapt to regular
- Result: 0-5% MPG reduction on regular
- Examples: Mazda3 Turbo, Honda Accord 2.0T, some Ford EcoBoost engines
Vehicles designed for regular (87 octane):
- No benefit from premium (engine not designed to take advantage)
- Result: 0% MPG improvement, wasted money
- Examples: Most mainstream cars (Toyota Camry 4-cyl, Honda Civic, Mazda CX-5 base)
Economic analysis: Premium costs ~$0.40-$0.60 more per gallon. A 3% MPG improvement rarely offsets the price premium.
Conversion Table: Miles per Gallon (UK) to Miles per Gallon (US)
| Miles per Gallon (UK) (MPG (UK)) | Miles per Gallon (US) (MPG (US)) |
|---|---|
| 0.5 | 0.416 |
| 1 | 0.833 |
| 1.5 | 1.249 |
| 2 | 1.665 |
| 5 | 4.163 |
| 10 | 8.327 |
| 25 | 20.817 |
| 50 | 41.634 |
| 100 | 83.267 |
| 250 | 208.169 |
| 500 | 416.337 |
| 1,000 | 832.674 |
People Also Ask
How do I convert Miles per Gallon (UK) to Miles per Gallon (US)?
To convert Miles per Gallon (UK) to Miles per Gallon (US), enter the value in Miles per Gallon (UK) in the calculator above. The conversion will happen automatically. Use our free online converter for instant and accurate results. You can also visit our fuel consumption converter page to convert between other units in this category.
Learn more →What is the conversion factor from Miles per Gallon (UK) to Miles per Gallon (US)?
The conversion factor depends on the specific relationship between Miles per Gallon (UK) and Miles per Gallon (US). You can find the exact conversion formula and factor on this page. Our calculator handles all calculations automatically. See the conversion table above for common values.
Can I convert Miles per Gallon (US) back to Miles per Gallon (UK)?
Yes! You can easily convert Miles per Gallon (US) back to Miles per Gallon (UK) by using the swap button (⇌) in the calculator above, or by visiting our Miles per Gallon (US) to Miles per Gallon (UK) converter page. You can also explore other fuel consumption conversions on our category page.
Learn more →What are common uses for Miles per Gallon (UK) and Miles per Gallon (US)?
Miles per Gallon (UK) and Miles per Gallon (US) are both standard units used in fuel consumption measurements. They are commonly used in various applications including engineering, construction, cooking, and scientific research. Browse our fuel consumption converter for more conversion options.
For more fuel consumption conversion questions, visit our FAQ page or explore our conversion guides.
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🔢 Conversion Formulas
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⚖️ Metric vs Imperial
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⚠️ Common Mistakes
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View all Fuel Consumption conversions →Other Fuel Consumption Units and Conversions
Explore other fuel consumption units and their conversion options:
- Kilometers per Liter (km/L) • Miles per Gallon (UK) to Kilometers per Liter
- Liters per 100 Kilometers (L/100km) • Miles per Gallon (UK) to Liters per 100 Kilometers
- Miles per Liter (mi/L) • Miles per Gallon (UK) to Miles per Liter
- Kilometers per Gallon (US) (km/gal (US)) • Miles per Gallon (UK) to Kilometers per Gallon (US)
- Kilometers per Gallon (UK) (km/gal (UK)) • Miles per Gallon (UK) to Kilometers per Gallon (UK)
Verified Against Authority Standards
All conversion formulas have been verified against international standards and authoritative sources to ensure maximum accuracy and reliability.
US Environmental Protection Agency — Official fuel economy measurement standards
Last verified: February 19, 2026