Gas prices seem to rise when you least expect them to, and drop right after you’ve filled your tank. So, GOBankingRates turned to artificial intelligence to answer a surprisingly tricky question: “What’s the best day to buy gas?”
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ChatGPT, OpenAI’s popular AI tool, had some insightful (and surprisingly practical) advice on gas prices and ideal times to head to the pump. Here’s what it had to say.
Buy on Monday or Friday — Avoid Wednesday and Thursday
According to ChatGPT, gas prices tend to be lowest at the beginning of the week, particularly on Monday. “This is typically when demand is lower and gas stations adjust prices downward to compete,” the AI explained. It also flagged Friday as another decent option, as stations may try to entice weekend travelers before any last-minute price hikes.
In contrast, Wednesday and Thursday are often poor choices. “Prices are more likely to rise midweek due to increased demand and wholesale price adjustments,” ChatGPT warned. So, if you tend to top off your tank midweek, you might be spending more than necessary.
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Fill Up in the Morning, Not the Evening
Beyond the day of the week, the time of day you fill up also matters — and for a reason you might not expect. ChatGPT recommended fueling up in the morning, when temperatures are cooler. Gasoline is denser at lower temperatures, meaning you technically get more energy per gallon.
“During the heat of the day, fuel expands slightly,” it pointed out. “While the price per gallon stays the same, you may actually get slightly less fuel by volume.” Though this difference is minor, it can add up over time, especially during hot summer months.
Other Smart Fuel Tips from ChatGPT
ChatGPT also emphasized avoiding last-minute fill-ups when your tank is nearly empty, as that leaves you at the mercy of whatever station is nearby — regardless of price. It also recommended using apps like GasBuddy or Waze to compare local prices in real time.
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This article originally appeared on GOBankingRates.com: ChatGPT Suggests 2 Best Days To Buy Gas — Here’s How To Maximize Savings
