Free tool, runs in your browser
Diesel budget buffer: how many cents to hold in reserve
Fuel budgets break when diesel jumps. This tool takes the weekly retail price history, measures how far it rose over 4, 8, 13 or 26 weeks, and turns a percentile of those rises into cents a gallon, dollars per 1,000 gallons and dollars for your own fleet.
Weekly seriesEIA retail on-highway diesel, weekly, since Jan 2, 2012Data as of the week of Oct 5, 2026 (latest EIA week in this snapshot)Retrieved Oct 10, 2026, 05:56 UTCretrieved Oct 10, 2026
Read this first
The buffer is a historical spread, not a forecast. Overlapping windows are not independent, so treat the percentile as a rough reserve and not as a probability you can bank. EIA publishes regional averages, not your pump price. Prices are nominal dollars per gallon.
Size your reserve
Pick the region, the horizon, how far back to look and the percentile. Add your fleet to see dollars.
Rolling change over the horizon you pick
Each point is the price change over the following weeks starting that week. Dashed line: the buffer. Dotted: zero.
Percentiles of those changes
Bars are P50, P75, P90 and P95. The selected percentile is highlighted.
Pre-filled values are Example data. Replace them with your own.
Buffer, cents per gallon
-
- Per 1,000 gallons
- -
- Your gallons over the horizon
- -
- Gross reserve for your fleet
- -
- After the share you recover
- -
- Net reserve per mile
- -
Enter your fleet.
Formula: buffer = percentile of (price after the horizon minus price at the start). Dollars = buffer x gallons. Gallons = trucks x miles / mpg, scaled to the horizon. Integer cents, rounded once. Nothing you type leaves this page.
The 90th-percentile buffer, U.S.
Cents a gallon by horizon and look-back. The last column is dollars on 1,000 gallons for the 5-year window.
| Horizon | Last 3 years | Last 5 years | Last 10 years | Dollars per 1,000 gal (5 years) |
|---|---|---|---|---|
| 4 weeks | 30 c | 37 c | 24 c | $365 |
| 8 weeks | 78 c | 71 c | 37 c | $708 |
| 13 weeks | 123 c | 138 c | 50 c | $1,376 |
| 26 weeks | 160 c | 167 c | 101 c | $1,667 |
Source: EIA open data API v2, series EMD_EPD2D_PTE_NUS_DPG, retrieved Oct 10, 2026. Nearest-rank percentile of the change in the weekly price over the horizon, for each start week in the look-back.
By region, 13 weeks, last 5 years
The same measure for each EIA region. A region with a bigger spread needs a bigger reserve.
| Region | Median rise | 90th percentile | Dollars per 1,000 gal | Latest price |
|---|---|---|---|---|
| U.S. | -3 c | 138 c | $1,376 | $6.199 |
| East Coast | -1 c | 131 c | $1,312 | $5.951 |
| Midwest | -2 c | 128 c | $1,279 | $6.286 |
| Gulf Coast | -2 c | 131 c | $1,308 | $5.819 |
| Rocky Mountain | -5 c | 116 c | $1,156 | $6.267 |
| West Coast | -5 c | 134 c | $1,344 | $7.229 |
Source: EIA open data API v2, retrieved Oct 10, 2026. Latest week Oct 5, 2026.
What it means for your fleet
- Budget diesel with a range, not a point. A reserve at the 90th percentile covers most of the history, not all of it.
- Match the horizon to the promise. A 4-week quote needs the 4-week figure. A contract rate you cannot reopen for 6 months needs the 26-week one.
- Check what the surcharge actually recovers. A schedule with a high peg or a step table can leave part of a rise on you. The recovery share in the form is yours to set.
- Look at the regional figure you buy in. The U.S. average hides a wider spread on the West Coast than elsewhere in some years.
- Repeat it each quarter. The window moves, and a calm year makes the reserve look smaller than it should.
Questions
What is the buffer?
It is a number from history. We take every 13-week (or 4, 8, 26-week) change in the weekly retail diesel price over the window you pick, sort them and read off a percentile. The 90th percentile says: in 9 of 10 start weeks the price rose by no more than this. It is not a forecast and it can be exceeded.
Why cents per 1,000 gallons?
A fleet buys diesel in volume, so a cent move is easier to think about as dollars on a round quantity. One cent a gallon is $10 on 1,000 gallons. The tool also converts it to your own gallons.
Which price is it?
The EIA weekly retail on-highway diesel average for the U.S. or a region, in dollars per gallon. It is not your pump price, your card discount or the index in your contract.
What does recovery mean?
It is the share of a fuel price rise you expect to get back through a fuel surcharge or rate. We do not suggest a figure. The 60% in the form is an example only.
How current is it?
The snapshot was retrieved Oct 10, 2026, latest EIA week Oct 5, 2026. The percentiles are computed from weekly prices since Jan 2, 2012.
Related guides and tools
- Fuel surcharge check: verify the broker schedule
- Diesel sensitivity: what a price move does to margin
- Diesel prices: weekly EIA series by region
- Diesel seasonality: which months are dearer
- Cost per mile: your own cost per mile
- All tools: free calculators
See what your last 20 loads show.
One short form. We reply by email with the next step, and a one-page report follows. Free, no obligation.
Mon-Fri, 9:00 a.m.-5:00 p.m. Eastern Time (Raleigh, NC). Voicemail is answered the next business day.