About & methodology
Exact sources, update cadence, and what this site will not do
What this site is
Weekly Diesel republishes the U.S. Energy Information Administration's weekly retail on-highway diesel price — the number freight contracts call “the DOE index” — for the U.S. average and all 10 EIA regions, with history to 1994, free CSVs, and fuel-surcharge math. It exists so that owner-operators, dispatchers, and brokers can check Monday's number and their lane's surcharge in one place.
Sources
Primary: USDA AgTransport public mirror of the EIA series
(Socrata dataset x88w-atzp,
“Weekly On-Highway Diesel Fuel Prices”):
https://agtransport.usda.gov/Fuel/Weekly-On-Highway-Diesel-Fuel-Prices/x88w-atzp
API endpoint queried each build:
https://agtransport.usda.gov/resource/x88w-atzp.json
Origin of the data: EIA's weekly on-highway diesel price survey, published at https://www.eia.gov/petroleum/gasdiesel/ (methodology: https://www.eia.gov/petroleum/gasdiesel/diesel_proc-methods.php). Prices are averages of a Monday retail survey, dollars per gallon including taxes. U.S. government data, public domain.
Update cadence & staleness guard
EIA releases the survey weekly, normally Monday/Tuesday (federal-holiday weeks slip a day). This site rebuilds on each release. Every build cross-checks the mirror's latest week and U.S. price against EIA's own release page; the build fails rather than publish if the mirror lags the current EIA release by more than 8 days, if the same-week prices disagree, or — when the EIA page is unreachable — if the mirror's latest week is more than 14 days old. So a number you see here is never silently stale. Latest build cross-check: EIA release “July 21, 2026”, week of , U.S. price $5.134 — matched the mirror exactly.
Method notes
Week-over-week change compares consecutive survey weeks. Year-over-year compares the closest survey week to 364 days earlier. Annual averages are simple means of the weekly readings (partial years marked). Regional series start later than the U.S. series where EIA introduced the split (PADD 1A/1B/1C in 1997, West Coast less California in 2011); California weekly data begins 1995. Nothing is interpolated or seasonally adjusted.
What this site does not do
No forecasts, no buy/sell or rate advice, no invented statistics. The fuel-surcharge calculator and matrix are reference math from the published index — your contract's base price and divisor always govern. This site is independent and not affiliated with the U.S. Department of Energy, the EIA, or the USDA.
Contact
contact@weeklydiesel.com — corrections welcome and fixed fast.