Semi Truck Fuel Cost Calculator
Fuel Cost = (Distance ÷ MPG) × Price Per Gallon. Enter your trip distance, your real MPG and today's diesel price to get gallons needed, the trip total, and your fuel cost per mile — plus what happens if diesel moves against you.
The short answer: semi truck fuel cost is (Distance ÷ MPG) × Price Per Gallon, and fuel cost per mile is simply Price Per Gallon ÷ MPG. At the U.S. Energy Information Administration weekly on-highway diesel average of $5.257 a gallon for the week ending August 10, 2026, a 1,000-mile trip at 6.0 MPG burns 166.7 gallons, costs $876.17 in fuel, and works out to $0.876 per mile. Change any one of those three inputs in the calculator below and every figure updates.
Diesel prices on this page checked against EIA on 11 August 2026. Reviewed by the Truck Dispatch Experts dispatch team.
How to Calculate Semi Truck Fuel Cost
Three equations cover everything on this page. They are the same arithmetic written three ways, so use whichever answers the question you are actually asking.
Gallons = Distance ÷ MPG
Fuel Cost = (Distance ÷ MPG) × Price Per Gallon
Fuel Cost Per Mile = Price Per Gallon ÷ MPG
The variables. Distance is the routed miles you will actually drive, including the empty leg to the pickup. MPG is your truck's real miles per gallon from your own receipts and odometer, not the sticker figure. Price Per Gallon is what you pay at the pump after any fuel-card discount — which is often below the retail average EIA publishes.
- 1
Work out the trip distance
Use the routed miles you will actually drive, not straight-line miles, and include the deadhead leg to the pickup. A 1,000-mile trip is the example used throughout this page.
- 2
Divide distance by your MPG to get gallons
Gallons = Distance / MPG. At 6.0 MPG a 1,000-mile trip burns 166.7 gallons. Use your own fuel receipts and odometer for MPG, not the sticker figure or a forum average.
- 3
Multiply gallons by the price you pay per gallon
Fuel Cost = Gallons x Price Per Gallon. At the EIA weekly U.S. on-highway diesel average of $5.257 a gallon for the week ending 10 August 2026, 166.7 gallons costs $876.17.
- 4
Divide the fuel cost by distance to get cost per mile
Fuel Cost Per Mile = Price Per Gallon / MPG, which is the same as total fuel cost divided by distance. $5.257 divided by 6.0 MPG is $0.876 per mile.
- 5
Re-run it at a higher diesel price before you commit
Add $0.50 to $1.00 a gallon and check the trip still pays. On the same 1,000-mile run at 6.0 MPG, a dollar a gallon is the difference between $876.17 and $1,042.83 of fuel.
Fuel is only one line of your cost base. Once you have this number, feed it into the trucking cost per mile calculator to get the breakeven rate you can actually quote a broker.
Fuel Cost Calculator: Gallons, Trip Total and Cost Per Mile
Trip Details
Fuel price defaults to $5.257/gal — the U.S. Energy Information Administration weekly retail on-highway diesel average for the week ending August 10, 2026. Replace it with what you actually pay at the pump, after any fuel-card discount.
Typical MPG by Equipment — and What It Costs Per Mile
| Equipment | MPG | Fuel $/mi at $5.257 |
|---|---|---|
| Dry Van (loaded) | 5.5-6.5 | $0.81–$0.96 |
| Reefer (loaded, unit running) | 4.5-5.5 | $0.96–$1.17 |
| Flatbed (loaded) | 5.0-6.0 | $0.88–$1.05 |
| Hotshot (loaded) | 8.0-12.0 | $0.44–$0.66 |
| Box Truck (loaded) | 8.0-14.0 | $0.38–$0.66 |
| Bobtail (no trailer) | 8.0-10.0 | $0.53–$0.66 |
These MPG ranges are operator rules of thumb for sizing a trip, not survey data — we do not have a published source for them and you should not treat them as one. For a measured benchmark, the North American Council for Freight Efficiency's Annual Fleet Fuel Study put its participating fleets at 7.77 MPG in 2023, against a Federal Highway Administration combination-truck figure of 6.91 MPG for 2022. Your own fuel receipts and odometer beat every number on this list.
What Diesel Costs Right Now: National and Regional Prices
The U.S. Energy Information Administration publishes a weekly retail on-highway diesel price every Monday. For the week ending August 10, 2026 the national average was $5.257 a gallon. EIA also breaks that down by refining region, and the spread is wide enough to change whether a lane works.
| Region | Diesel $/gal | Fuel $/mi at 6.0 MPG |
|---|---|---|
| California | $6.618 | $1.103 |
| West Coast (PADD 5) | $6.033 | $1.006 |
| Central Atlantic (PADD 1B) | $5.535 | $0.922 |
| West Coast less California | $5.526 | $0.921 |
| New England (PADD 1A) | $5.514 | $0.919 |
| Rocky Mountain (PADD 4) | $5.271 | $0.878 |
| U.S. national average | $5.257 | $0.876 |
| East Coast (PADD 1) | $5.193 | $0.865 |
| Midwest (PADD 2) | $5.181 | $0.864 |
| Gulf Coast (PADD 3) | $5.044 | $0.841 |
| Lower Atlantic (PADD 1C) | $5.034 | $0.839 |
Source: U.S. Energy Information Administration, Weekly Retail On-Highway Diesel Prices, week ending August 10, 2026, checked 11 August 2026. All prices include taxes. The per-mile column is that price divided by 6.0 MPG — our arithmetic, not an EIA figure.
Why the regional table matters. California diesel is $1.574 a gallon more expensive than Gulf Coast diesel in the same week. On a 1,000-mile run at 6.0 MPG that is 166.7 gallons, so fuelling in California instead of the Gulf Coast costs roughly $262 more for identical miles. A calculator that only knows the national average hides that entirely.
Where you buy fuel also changes what you owe at quarter end, because IFTA settles the difference between the fuel tax you paid and the tax due on the miles you ran in each jurisdiction. Run the numbers in our IFTA calculator and read the IFTA filing guide before you build a fuel-buying strategy around price alone. Our best and worst states for trucking breakdown covers the wider state-by-state cost picture, and the 2026 diesel price outlook tracks where the national number is heading.
Context for the year: EIA's weekly national average has run between $3.46 and $5.64 across 2026 and averaged $4.80. Any fuel figure you carry in a spreadsheet for more than a month or two is wrong by a margin that matters.
Fuel Cost Per Mile by Equipment Type
Same diesel price, very different bills. The MPG ranges below are the sizing figures operators commonly use, and the two money columns are those ranges divided into $5.257 a gallon, then multiplied out to a 10,000-mile month so the number feels like something you would recognise on a statement.
| Equipment | Typical MPG | Fuel $/mi | Fuel / month at 10,000 mi |
|---|---|---|---|
| Dry van (loaded) | 5.5 – 6.5 | $0.81 – $0.96 | $8,090 – $9,560 |
| Reefer (loaded, unit running) | 4.5 – 5.5 | $0.96 – $1.17 | $9,560 – $11,680 |
| Flatbed (loaded) | 5.0 – 6.0 | $0.88 – $1.05 | $8,760 – $10,510 |
| Hotshot (loaded) | 8.0 – 12.0 | $0.44 – $0.66 | $4,380 – $6,570 |
| Box truck (loaded) | 8.0 – 14.0 | $0.38 – $0.66 | $3,760 – $6,570 |
| Bobtail (no trailer) | 8.0 – 10.0 | $0.53 – $0.66 | $5,260 – $6,570 |
Read this honestly: the MPG ranges are operator rules of thumb we use for sizing, not survey data, and we have no published source for them — please do not quote them as one. The dollar columns are pure arithmetic on those ranges at $5.257 a gallon. For a measured benchmark, the North American Council for Freight Efficiency Annual Fleet Fuel Study reported participating fleets averaging 7.77 MPG in 2023, against a Federal Highway Administration combination-truck figure of 6.91 MPG for 2022.
For scale against total operating cost: the American Transportation Research Institute put the industry-average marginal cost of running a truck at $2.336 per mile in 2025, and $1.854 per mile excluding fuel, in its 2026 Analysis of the Operational Costs of Trucking released 15 July 2026. The difference implies about $0.482 a mile of fuel across 2025 — our subtraction, not an ATRI line item. Diesel is materially higher in 2026, which is exactly why this calculator derives fuel from today's price instead of carrying a fixed cents-per-mile figure.
Reefer Fuel: You Are Paying for Two Engines, Not One
A reefer run has two separate fuel costs and most trip estimates only count the first. The tractor burns diesel to move the load, and the refrigeration unit burns diesel to hold temperature — including while you sleep, while you wait at a receiver, and while the truck is shut down. EPA describes transport refrigeration units as most often powered by small diesel engines, separate from the truck engine.
That second burn never shows up in your tractor MPG, so it never shows up in a standard fuel calculation either. We are not going to publish a gallons-per-hour figure for reefer units, because we could not find a primary source we trust for one and this network has been burned before by numbers that got quoted back as fact. Do it properly instead:
- Keep reefer fuel on its own line in your fuel log, separate from tractor fuel.
- Divide a month of reefer gallons by that month's loaded miles to get your own reefer cost per mile, then add it to the tractor figure from the calculator above.
- Quote reefer freight against the combined number. A rate that clears dry-van fuel does not automatically clear reefer fuel.
Our reefer vs dry van profitability breakdown covers the rest of the comparison — higher rates, higher insurance, higher claim risk — so you can judge the segment on the whole picture rather than fuel alone.
What Idling Costs You Per Night, Per Month and Per Year
This is the cheapest fuel saving available to most owner-operators, and the only one on this page where a federal agency has done the measuring. The U.S. Department of Energy states plainly that idling a heavy-duty truck consumes about 0.8 gallon of fuel per hour, and that a long-haul truck typically idles about 1,800 hours a year, using about 1,500 gallons of diesel. Argonne National Laboratory estimates that U.S. rest-period truck idling consumes up to 1 billion gallons of fuel annually, at a cost of around $3 billion.
Put the current diesel price against those hours and the numbers stop being abstract. Every figure in the table below is 0.8 gallon an hour multiplied by $5.257 a gallon.
| Idling period | Gallons burned | Cost at $5.257/gal |
|---|---|---|
| 8-hour rest period | 6.4 gal | $33.64 |
| 10-hour rest period | 8.0 gal | $42.06 |
| Seven 8-hour nights (one week) | 44.8 gal | $235.51 |
| 6 hrs/day for 30 days | 144 gal | $757.01 |
| 8 hrs/day for 30 days | 192 gal | $1,009.34 |
| 1,800 hrs/year (DOE typical long-haul figure) | ~1,500 gal | ~$7,890 |
Idle rate, annual hours and annual gallons: U.S. Department of Energy, Vehicle Technologies Office / Clean Cities, Long-Haul Truck Idling Burns Up Profits, which also carries the Argonne National Laboratory estimate. Dollar figures are those gallons multiplied by the EIA price of $5.257/gal for the week ending August 10, 2026— our arithmetic, not a DOE figure.
An owner-operator idling six to eight hours a night is spending roughly $757 to $1,009 a month on fuel that moves the truck exactly nowhere. That is the number to hold an APU, a bunk heater or a battery cooling system against — DOE notes that alternatives to idling can use up to 95% less fuel. Note also that many states and municipalities restrict heavy-duty idling outright, so the fuel is not the only exposure.
Deadhead Miles Change Your Real Fuel Cost Per Paid Mile
A single-MPG trip estimate quietly assumes every mile is a loaded, paid mile. Real trips are not built that way. You run empty to the pickup, you burn fuel doing it, and nobody pays you for those miles — which means your fuel cost per paid mile is higher than the calculator's headline figure.
Worked example. 800 loaded miles at 6.0 MPG plus 200 empty miles at an assumed 7.0 MPG. That is 133.3 gallons loaded and 28.6 gallons empty, 161.9 gallons in total, which is $851.13 of fuel at $5.257 a gallon. The broker pays for 800 miles, so your real fuel cost is $1.064 per paid mile — not the $0.876 you would get by dividing across all 1,000. That is 21% more, and it is the difference between a load working and a load not working. Swap in your own empty MPG; 7.0 is an assumption, not a published figure.
Measure the empty leg properly with the deadhead miles calculator, then work on bringing the percentage down with our guide to avoiding deadhead. Deadhead is usually the fastest lever on fuel cost per paid mile, because it does not require you to change a single thing about how you drive.
Recovering Fuel Cost: How a Fuel Surcharge Works
Everything above tells you what fuel costs. A fuel surcharge (FSC) is the mechanism for getting it back. It exists because a rate agreed today can be hauled three weeks from now at a completely different diesel price, and without an FSC clause that entire swing lands on the carrier.
Fuel Surcharge Per Mile = (Current Diesel Price − Base Diesel Price) ÷ MPG
Worked through. Say your contract sets a base of $3.00 a gallon — the price at which the linehaul rate alone is meant to cover fuel — and your truck runs 6.0 MPG. With diesel at the EIA weekly average of $5.257, the surcharge is ($5.257 − $3.00) ÷ 6.0 = $0.376 per mile, or $376.17 on a 1,000-mile load. The base price and the MPG are contract terms you negotiate; the current price should be tied to the published EIA weekly figure so nobody has to argue about which number applies.
Two things to watch. First, an FSC pegged to a base far above today's reality pays you almost nothing — check the base, not just the presence of a clause. Second, the MPG in the formula is the broker's assumption about your truck; a higher assumed MPG shrinks your surcharge. Both are negotiable, and both are worth more than haggling over the linehaul. Our rate negotiation tips cover how to raise them, and the rate per mile calculator shows what the all-in number needs to be.
How to Cut Your Fuel Bill, in Order of What It Is Worth
Ranked by how much money each one actually moves for a typical owner-operator, and deliberately light on precise percentages where we do not have a source that supports them.
- Stop idling overnight. The only item on this list with a federal measurement behind it: DOE puts heavy-duty idling at about 0.8 gallon an hour, which is $757 to $1,009 a month at six to eight hours a night. An APU, a bunk heater or an electrified parking space attacks that directly.
- Cut empty miles. Deadhead raises your fuel cost per paid mile without changing your MPG at all — see the worked example above, and the deadhead calculator.
- Slow down on long highway runs. Aerodynamic drag rises steeply with road speed, so a lower cruise speed burns less fuel over the same distance. Test it on your own lanes over a full month rather than trusting a rule of thumb — including the rules of thumb you will find quoted everywhere with no source attached.
- Buy fuel where it is cheaper, carefully. The regional table above shows a $1.57 a gallon spread in a single week. Fuel-network discounts move your real price further below the retail average. Just remember IFTA settles the tax difference, so plan with the IFTA calculator rather than pump price alone.
- Keep tyres inflated and the truck maintained. Underinflated tyres increase rolling resistance, and a neglected engine, air filter or injector set costs MPG. The truck maintenance schedule guide sets the intervals.
More detail on the driving habits themselves is in our fuel saving tips for truck drivers.
Is the Rate Worth It? Fuel Cost vs Load Rate
This is the decision the calculator exists to serve. Fuel is not a number you look at for its own sake — it is the first thing you subtract from a rate offer to see what is left.
Worked example. DAT's national dry van spot average was around $3.00 a mile including fuel as of July 2026. On a 1,000-mile load that is $3,000 of revenue. Subtract $876.17 of fuel at 6.0 MPG and $5.257 a gallon and you are left with $2,123.83 to cover the truck payment, insurance, maintenance, tyres, tolls, permits, factoring and dispatch fees, and whatever you intend to pay yourself. Fuel alone ate 29% of the gross.
Now run the same load with 200 miles of deadhead, or at 5.5 MPG instead of 6.0, or with California diesel instead of Gulf Coast, and the picture shifts by hundreds of dollars. That is the whole reason to check before you accept rather than after you deliver.
Take it the rest of the way with the profit per load calculator, set a floor you will not book below using the cost per mile calculator, and browse everything else on the trucking calculators hub. If you would rather not do this arithmetic on every load, our owner-operator dispatch guide explains how a dispatcher handles it for you.
Frequently Asked Questions
How do I calculate fuel cost for a trucking trip?
Fuel Cost = (Distance / MPG) x Price Per Gallon. Divide the trip distance by your truck's MPG to get gallons, then multiply by what you pay per gallon. Worked through at the EIA weekly U.S. on-highway diesel average of $5.257 a gallon for the week ending 10 August 2026: a 1,000-mile trip at 6.0 MPG burns 166.7 gallons and costs $876.17 in fuel, which is $0.876 per mile.
How much does fuel cost per mile for a semi truck?
Fuel cost per mile = diesel price per gallon divided by MPG. At the EIA national average of $5.257 a gallon for the week ending 10 August 2026, a truck running 6.0 MPG spends $0.876 a mile on fuel, 6.5 MPG spends $0.809, and 5.5 MPG spends $0.956. A loaded reefer at 4.5 MPG spends $1.17 a mile.
How much fuel does a semi truck use per 100 miles?
Divide 100 by your MPG. A loaded dry van running 5.5 to 6.5 MPG uses roughly 15.4 to 18.2 gallons per 100 miles. At the EIA national diesel average of $5.257 a gallon for the week ending 10 August 2026, that is about $81 to $96 of fuel every 100 miles.
What MPG should I use for my truck?
Use your own fuel receipts and odometer, because equipment, weight, terrain and driving style move the number more than any published average. As rough sizing figures only, loaded dry vans commonly run 5.5 to 6.5 MPG, reefers with the unit running 4.5 to 5.5, flatbeds 5.0 to 6.0, hotshots 8.0 to 12.0 and a bobtail tractor 8.0 to 10.0. For a measured benchmark rather than a rule of thumb, the North American Council for Freight Efficiency's Annual Fleet Fuel Study reported its participating fleets averaged 7.77 MPG in 2023, against a Federal Highway Administration combination-truck figure of 6.91 MPG for 2022.
Where does the diesel price in this calculator come from?
The default is the U.S. Energy Information Administration's Weekly Retail On-Highway Diesel Price for the United States, which was $5.257 a gallon for the week ending 10 August 2026. EIA publishes it every Monday alongside a regional breakdown, and this page carries both. Replace the default with what you actually pay at the pump after any fuel-card discount.
How much fuel does a semi truck burn while idling?
The U.S. Department of Energy states that idling a heavy-duty truck consumes about 0.8 gallon of fuel per hour. An 8-hour rest period is therefore about 6.4 gallons, roughly $34 at the EIA national diesel average of $5.257 a gallon for the week ending 10 August 2026. DOE also reports that a long-haul truck typically idles about 1,800 hours a year, using about 1,500 gallons of diesel, which is about $7,890 a year at the same price.
How much more does a reefer cost to fuel than a dry van?
Two ways. The tractor pulling a loaded reefer generally returns lower MPG than the same tractor on a dry van, and the refrigeration unit is a separate small diesel engine with its own fuel draw. EPA describes transport refrigeration units as most often powered by small diesel engines, independent of the truck engine. That second burn does not show up in your MPG at all, so track reefer fuel as its own line on your receipts rather than assuming tractor MPG covers it.
Should I factor DEF into my fuel cost per mile?
Yes, as a separate line. Trucks with selective catalytic reduction after-treatment consume diesel exhaust fluid alongside diesel, and you buy it separately from your fuel. We do not publish a consumption ratio here because we have no primary source for one; work out your own by dividing the DEF gallons on your receipts by the diesel gallons over the same period, then multiply by the DEF price you pay.
How does route terrain and load weight affect my trip fuel cost?
Both change the MPG input rather than the formula. Heavy loads, sustained grades, headwinds, stop-and-go city miles and cold-weather idling all pull MPG down, and a tenth of an MPG is real money at current diesel prices. The practical fix is to keep separate MPG figures for the lane types you actually run, rather than one blended number, and enter the right one before pricing a load.
How do I calculate a fuel surcharge per mile?
The standard formula is (Current Diesel Price - Base Diesel Price) / MPG. If your contract sets a base of $3.00 a gallon, diesel is at the EIA weekly average of $5.257, and your truck runs 6.0 MPG, the surcharge is ($5.257 - $3.00) / 6.0 = $0.376 per mile, or $376.17 on a 1,000-mile load. Tie the current price to the published EIA weekly figure so neither side has to argue about which price applies.
How can I improve my truck's fuel economy?
The two levers with the clearest evidence behind them are cutting idle time and slowing down. DOE puts heavy-duty idling at about 0.8 gallon an hour, so an APU or bunk heater attacks a cost you can actually measure. Aerodynamic drag rises steeply with road speed, so holding a lower cruise speed on long highway runs reduces burn. Beyond that: keep tyres correctly inflated to limit rolling resistance, stay on the maintenance schedule, and plan lanes that cut empty miles.
What is a break-even diesel price and why does it matter?
It is the diesel price at which a load stops making money. Because you fuel over the course of a trip rather than all at once, a point estimate at today's price understates your risk on a multi-day haul. EIA's weekly national diesel average ranged from $3.46 to $5.64 across 2026 and averaged $4.80, so re-run any long trip at current price plus $0.50 to $1.00 a gallon before you accept it.
Methodology and Sources
Every number on this page is one of three things: a figure from a named external source, arithmetic shown openly on the page, or an example input you are expected to replace with your own. Nothing here is an estimate we invented to fill a gap.
- Diesel $5.257/gal and every regional price. U.S. Energy Information Administration, Weekly Retail On-Highway Diesel Prices, week ending August 10, 2026. Checked 11 August 2026. Prices include taxes.
- 2026 diesel range $3.46 to $5.64, average $4.80. Same EIA weekly series, 2026 readings to date.
- Idling at 0.8 gallon per hour, 1,800 hours and 1,500 gallons a year, Argonne's 1 billion gallon / $3 billion national estimate. U.S. Department of Energy, Vehicle Technologies Office / Clean Cities, Long-Haul Truck Idling Burns Up Profits. The dollar conversions are ours.
- Fleet MPG benchmarks 7.77 MPG (2023) and 6.91 MPG (2022). North American Council for Freight Efficiency, Annual Fleet Fuel Study; the 6.91 figure is Federal Highway Administration combination-truck fuel economy as cited in that study.
- $2.336 and $1.854 per mile operating cost. American Transportation Research Institute, 2026 Analysis of the Operational Costs of Trucking, released 15 July 2026, covering 2025. The implied $0.482 a mile of fuel is our subtraction, not an ATRI line item.
- Reefer units powered by separate small diesel engines. U.S. Environmental Protection Agency, Refrigerated Trailers and Transport Refrigeration Units.
- Dry van spot rate $3.00 a mile. DAT national average including fuel, as of July 2026.
- MPG ranges by equipment type, the 7.0 MPG empty-running assumption, and the $3.00 fuel-surcharge base. Example inputs and operator rules of thumb, not sourced data. They are here to make the worked examples reproducible. Replace them with your own figures.
Page and calculator defaults last reviewed 11 August 2026 by the Truck Dispatch Experts dispatch team. Diesel prices move weekly; re-check the EIA figure before pricing a long-haul load.
We Factor Fuel Into Every Load Decision
Our dispatchers calculate fuel costs, deadhead expenses, and net revenue for every load before presenting it to you. No surprises — just profitable miles.