Is tequila stronger than vodka is a question people often ask, as tequila is thought of as a stronger spirit while vodka is seen as a drink for beginners.
The answer to the question of whether tequila is stronger than vodka is that it depends. No one spirit is automatically stronger than another spirit in every situation. Most tequilas and vodkas will be the same strength, that is the accepted standard for the majority of spirits of 40% ABV, or 80 proof.
Why Are Most Spirits 80 Proof?
Spirits don't have to be 80 proof, although in the USA this is the minimum alcohol level allowed by law for spirits. You will find some spirits, like flavored vodkas or low-calorie spirits that are less than 80 proof, but they have to be clear about it. 80 proof just happens to be a figure that was a historic convention, but is also one that most spirits simply taste best at. Another factor is that alcohol is taxed according to its strength, so 80 proof spirits pay the least tax and therefore end up cheaper on the shelves and more profitable to make.
So, Is Tequila Stronger than Vodka?
The overwhelming majority of tequilas and vodkas are both bottled at 80 proof. This means that they all have exactly the same amount of alcohol in them. The alcohol is what gives you a headache and a hangover, if you drink too much. All things being equal, tequila can't give you a worse hangover than vodka, which is something people often claim. Drink the same amount of the same strength tequila and vodka - on different nights, of course! - and you will get the exact same degree of hangover, subject to how much water you might drink or how much food you might eat as well.
However, not all things are equal in the world of distilling. Whether you're distilling from potatoes or from agave plants, the part of the spirit you want is known as the heart. This is the good quality tasty stuff. What you don't want is the heads and the tails - the spirit that comes off first, and the spirit that comes off last. This is inferior quality and really will give you the worst headaches and hangover you've ever had. Too much of it and you can go blind or even die.
Getting rid of the heads and the tails costs time and money, but if you want to make the best-tasting spirits then you do it. If, on the other hand, you want to make the cheapest spirits you might care a little less about only going for the heart. Now, if your first experience of drinking tequila was in a bar in Cancun on Spring Break, and in the bar with the cheapest shots at that, do you think you were drinking good-quality tequila? Is it surprising it gave you a monumental hangover?
When Is Tequila Stronger than Vodka?
The only way that tequila is stronger than vodka is if you're comparing, say, a 90 proof tequila with an 80 proof vodka. Then you can definitely say that the tequila is 12% stronger than the vodka.
By and large, there are more examples of strong tequilas than strong vodkas. Vodka has been made at 80 proof for centuries, and though there are stronger vodkas around, it takes a lot of work to make them taste good too. Taking the same vodka and bottling it at more than 80 proof isn't automatically going to make it a better vodka, only a stronger one. Make it too strong and while it might give your cocktails a kick you wouldn't want to sip it neat or on the rocks.
Tequila is a whole other matter, though. Silver or blanco tequila is unaged tequila and is the agave equivalent of vodka, and almost always bottled at 80 proof. With tequilas that are aged in barrels, more complex flavors start to develop, and the more chances there are for distillers to experiment to see what tequilas they can produce. To understand this more, you might want to experiment at home by aging your own blanco tequilas for different lengths of time.
Variations include the type of barrel used, the length of time the spirit spends in the barrel, the blending of tequilas, and the strength you bottle them at. A distiller might sample a particular tequila at different strengths and decide that the 90 proof tastes better than the 80 proof. As vodka by its nature is unaged it isn't experimented upon like this. Once you start to age vodka, you're immediately turning it into another spirit, from Coconut Rum to Mexican Corn Whiskey.
The bottom line, to answer the question, is that tequila is not stronger than vodka automatically, but you're more likely to come across stronger tequilas than stronger vodkas.