your mileage may vary

The United States Environmental Protection Agency requires all new vehicles to undergo a set of standard emissions tests which simulate city and highway driving. Part of the test measures estimated city and highway gas (petrol) mileage estimates. Since no test can exactly simulate all driving habits and conditions, the actual gas mileage of each vehicle will vary. As a result, when these estimated mileage claims from automobile manufacturers appear in advertisements, they are almost always accompanied with the standard disclaimer “your mileage may vary”.

• "The battery lasts a day in my phone, but your mileage may vary."
• "When that definition is executed, the metadata for the temporary table is put into your schema (most likely—your mileage may vary), but no space is allocated to hold data."
• "In other words, your mileage may vary and my disk-size figures are just estimates provided for your convenience."
• "We pause here to emphasize that with animals, there are no absolutes. […] We like to say that with any given wolf or dog, "your mileage may vary.""
• "Mallory Ortberg: […] The advice game is the ultimate your-mileage-may-vary exercise—do you have a feeling for when someone is looking for (or needs) a gentle smack to return them to their senses, a bit of empathy, a dose of humor? It’s a tricky balance, I think, between writing something entertaining for your many readers and trying to be genuinely helpful to the original writer."
• "I think that red dress looks really good on you, but your mileage may vary, of course."
• "Your mileage may vary when it comes to the over-the-top carnage and in-your-face machismo, but it’s impressive just how bonkers Fate [The Fate of the Furious] is, like a litter of kittens hopped up on grade-A catnip."
• "The privatization of luxury space in planes, trains and automobiles have certainly enhanced our ability to keep to ourselves on the road (see the rise of personal pods at airports for a recent example of the lengths people will go to for solitude). And as those spaces get increasingly automated, human interaction is becoming increasingly limited (although your mileage may vary as to how much you really enjoy that interaction with customs or gate agents)."

• YMMV
• your mileage may differ
• YMMD

• YKINMK