Erase the idea that sleeping on a futon means sleeping on a thin, lumpy and just plain uncomfortable mattress. While that type of futon was popular in the 1970s, it’s come a long way since then. And much like dial-up internet or diesel-guzzling cars, that kind of futon has long since faded into history.

Today, you can find various comfortable futon mattresses in an array of sizes and prices ranging from about $100-$1,000. And unlike days gone by, you’re likely to get a great night’s sleep on any number of futon mattresses.

You may have a general knowledge about mattress sizes for beds, but sizing can differ when it comes to futon mattresses. Sizes can also vary among manufacturers, but here’s what you can expect from most brands.

A twin futon mattress will be about 38 inches by 75 inches. They can often fold up into a chair-style for easy seating. Twin-size futons are light, comfortable and perfect for the occasional guest. Twin futon mattresses come with and without ottomans. If you're in the market for this size, here's a great choice available at Amazon.

Full-size futon mattresses are typically about 54 inches by 75 inches. This is the standard size of a futon and often what people think of when they consider a futon mattress. Most full-size futon mattresses fold into love seats or small couches. They're generally wide enough for two adults. If you want a high-quality full-size mattress, this one is a great option and is available at Amazon.

The queen futon mattress is approximately 60 inches by 80 inches and can double as a regular bed for most adults and couples. This futon is generally firm enough for individuals of any weight. Since the queen size has more depth and volume, it's typically even more comfortable when folded up as a couch. This queen-size memory foam futon mattress is available at Kohl's.

If two adults plan to sleep on a futon, they may want to choose a king size. The king futon mattress is approximately 76 inches by 80 inches and can comfortably sleep two people. And with the king-size mattress even thicker than its predecessors, it makes for a very comfortable fold-up couch. Here's a great one at Wayfair. There are thinner king-size mattresses, too, including this high-quality one at Wayfair.

The California King is perfect for adults who want extra space to stretch. Measured at approximately 72-inch by 84-inch, California King futon mattresses are relatively hard to find and can be extra pricey. You can also opt for custom-sized futon mattresses. You'll be able to select your size and thickness for up to 10 inches. This California King is available at Wayfair.

Nancy Dunham is a writer for BestReviews. BestReviews is a product review company with a singular mission: to help simplify your purchasing decisions and save you time and money.

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