Data Sources & Methodology
Gas Price Today was founded on a simple pledge: never fabricate prices, never hide update dates, and never label weekly surveys as real-time quotes.
1. Daily State & National Fuel Prices
Daily Live BenchmarksOur current statewide and national gasoline and diesel price benchmarks are sourced from daily retail fuel surveys compiled by AAA (American Automobile Association) in partnership with the Oil Price Information Service (OPIS).
OPIS tracks fleet credit card transactions and direct station feeds from over 130,000 retail fueling stations across the United States. Daily averages reflect weighted retail cash and credit pump prices across Regular Unleaded, Mid-Grade, Premium, and Ultra-Low Sulfur Diesel (ULSD).
2. Multi-Year Historical Trends & Milestones
Official Federal DataOur multi-year historical trend charts and annual benchmarks (2021–2026) are compiled from the U.S. Energy Information Administration (EIA), an independent statistical agency within the U.S. Department of Energy, distributed via Federal Reserve Economic Data (FRED).
Every Monday, the EIA surveys a statistically selected representative sample of retail service stations across the country (Form EIA-878: Motor Gasoline Price Survey). This official time series ensures multi-year comparisons remain consistent, standardized, and audit-grade.
3. Why We Explicitly Label Data Frequencies
Many consumer websites claim to display "Live Gas Prices" when in reality they are republishing data that is days or weeks old without timestamps.
At Gas Price Today, every single price card carries a clear freshness indicator: Daily retail average (as of Date) for current AAA/OPIS state tables, and Weekly average — week ending (Date) for multi-year EIA historical records.
If pricing data for a particular fuel grade or territory is unavailable or statistically uncertain, our system displays Data unavailable rather than estimating or inventing a fictitious figure.
4. Fuel Specifications & Grade Definitions
Prices reported on Gas Price Today represent cash or credit retail averages for standard highway motor fuels:
Standard unleaded motor gasoline with an Anti-Knock Index (AKI) octane rating of 87. Includes up to 10% ethanol (E10) as standard in most U.S. markets.
Plus unleaded gasoline with an octane rating of 89, produced by blending regular and premium grades at the retail dispenser.
High-octane fuel with an AKI of 91 (common in Western/high-altitude states) or 93 (common in the East and Midwest), required for high-compression engines.
On-highway No. 2 diesel fuel containing a maximum of 15 parts per million (ppm) sulfur content for heavy-duty trucks, passenger cars, and commercial machinery.
5. Limitations of Averages
Statewide averages provide a macro benchmark for budgeting, trend analysis, and regional comparison. However:
- Intra-state variation: Gas prices in remote or high-tax localities may differ considerably from the statewide statistical median.
- Cash vs. Credit spreads: Some retail stations assess a surcharge for credit card transactions. Surveys capture weighted cash and credit averages.
- Station-level accuracy: Gas Price Today does not provide individual retail gas station listings.
6. Independent Operation & Non-Affiliation
Gas Price Today is an independent, ad-free web utility. We have no commercial or corporate affiliation with the American Automobile Association (AAA), the U.S. Energy Information Administration (EIA), GasBuddy, the Oil Price Information Service (OPIS), or the U.S. Department of Energy.