Crude oil futures are the most important oil futures in the world. At present, the most important oil futures contracts in the world mainly include the NYMEX York Mercantile Exchange's "West Texas Intermediate" futures contract, London International Petroleum Exchange's (IPE) high-sulfur crude oil futures contract, Singapore Exchange's (SGX) Brent crude oil futures contract and Dubai Acid crude oil futures contract.

The main classification indexes of crude oil in the world are API degree (light, medium and heavy according to API value) and sulfur content. In the existing crude oil reserves, medium and heavy crude oil is higher than light crude oil. According to the classification of sulfur content, low sulfur crude oil only accounts for 17%, sulfur crude oil accounts for 30.8%, and high sulfur crude oil accounts for 58%.

So what is the international crude oil index? The international crude oil index mostly adopts the synthesis of the main contract of NYMEX light and low sulfur crude oil futures contract. When the month of 1- 12 is the main contract, the crude oil index is quoted at the price of that month.

What are the international crude oil indexes? The world crude oil trade has formed three major markets in North America, Europe and Asia, and each market has crude oil with price indicators, namely WTI crude oil, Brent crude oil in the North Sea and Dubai crude oil produced in the Middle East. Among them, the best quality is WTI crude oil futures price, which refers to West Texas light crude oil in the United States and is a common crude oil futures price in North America. Due to the global military and economic capabilities of the United States, WTI crude oil has become the benchmark for global crude oil pricing.