The Basic Concept
To turn crude oil into the petrol and diesel drivers use, crude must pass through a refinery. Refiners buy crude at the Brent or WTI benchmark price and sell finished products — petrol (gasoline), diesel, jet fuel, heating oil, and fuel oil — at product-specific market prices. The crack spread is simply:
Crack Spread = Product Price − Crude Price
It is called a "crack spread" because crude is "cracked" — broken into lighter fractions — in the refinery process. A positive crack spread means refiners are profitable; a negative spread means they are losing money on each barrel processed.
The 3-2-1 Crack Spread
The industry standard shorthand is the 3-2-1 crack spread: assume 3 barrels of crude produce 2 barrels of petrol (gasoline) and 1 barrel of diesel/heating oil. Calculated against Brent crude and European product prices:
3-2-1 = (2 × Gasoline Price + 1 × Diesel Price − 3 × Crude Price) ÷ 3
In normal market conditions, the 3-2-1 crack spread trades between USD 10–25/barrel. At USD 20/barrel, this adds roughly USD 0.12–0.14/litre to the wholesale cost of petrol above the crude price.
CME Group publishes crack spread futures as actively traded contracts — both the RBOB gasoline crack (US) and the heating oil crack (closely watched as a diesel proxy).
The 2022 Diesel Crack Spread Spike
Crack spreads are usually background noise compared to crude price movements. 2022 was a dramatic exception. When Russia's invasion of Ukraine disrupted Russian middle distillate exports to Europe, and simultaneously European utilities switched from gas to diesel for power generation (see our Russia–Ukraine fuel prices article), the European diesel crack spread exploded from ~USD 15–20/barrel to over USD 60–70/barrel by June 2022.
This meant diesel pump prices rose far faster than petrol even when crude prices moved together — because the refinery margin component of diesel had tripled. By mid-2022, diesel was more expensive than petrol across most of Europe, reversing the normal relationship. The IEA Monthly Oil Market Reports from 2022 document this crack spread episode in detail.
Crack spreads measure the refinery margin, not the full retail price. Pump prices additionally include: distribution and retail margin, excise duty, VAT, and any government price control adjustments. The crack spread is the wholesale-level variable. Our guide on what makes up the price at the pump shows the full stack.
Regional Crack Spreads
Different regions have different crack spreads because product demand, refinery configuration, and crude quality vary:
- US Gulf Coast (USGC): Benchmarked against WTI crude, RBOB gasoline, and ULSD diesel. Tracked by EIA spot prices.
- Northwest Europe (NWE): Benchmarked against Brent, Eurobob gasoline, and gasoil (diesel). Prices reported daily by Argus Media and S&P Platts.
- Singapore: Benchmarked against Dubai/Oman crude, reflecting Asian refining economics. Singapore complex crack margins are closely watched for Asia-Pacific pump price signals.
Refinery Capacity and Structural Margins
Crack spreads are not just about day-to-day supply and demand — they are also shaped by the global refinery capacity picture. When refinery capacity is tight (high utilisation rates), margins tend to rise because any disruption has an outsized effect. The EIA US Refinery Capacity Report and the IEA Oil 2024 medium-term outlook project that refinery closures in advanced economies (several European refineries shut in 2020–2023) will structurally support crack spreads above pre-2020 norms through the late 2020s.
This is a significant long-run pump price driver that is independent of OPEC policy or crude supply. Even if crude prices were to fall, tight refinery capacity can keep the product-price component of pump prices elevated. Our guide on how analysts forecast fuel prices covers crack spreads as an input to professional forecasting models.
Frequently Asked Questions
What is a crack spread?
The price difference between crude oil and the refined products made from it (mainly petrol and diesel). It represents the gross refining margin. The standard "3-2-1 crack spread" assumes 3 barrels of crude yield 2 barrels of petrol and 1 barrel of diesel. Tracked by CME Group futures and EIA spot prices.
How do crack spreads affect pump prices?
Crack spreads are the refinery margin component of pump prices. When they widen, prices rise even if crude is flat. The 2022 diesel crack spread spike (USD 60–70/barrel in Europe) drove diesel above petrol prices across the continent. See the IEA Oil Market Reports for historical crack spread data.
Where can I track crack spreads?
CME Group crack spread futures, EIA weekly spot prices, and professional services like Argus Media and S&P Platts.