How we tested
Bento-style lunchboxes are compartmentalized containers inspired by the Japanese bento, a single-serving, portable, boxed meal that according to some sources dates back to the 12th century. In Japan, a traditional bento box commonly contained rice, pickled vegetables, and fish or meat, but today they often include a wide variety of foods—sometimes shaped and arranged to resemble cartoon characters, flowers, animals, or other objects.
But no matter the composition of your meal, a multicompartment, fairly compact container can be convenient. To find out which bento-style lunchbox is best, we selected six widely available models ranging in size, all under $40.00. Four had individual containers that stacked vertically; three of these were held together with an elastic band, while one had latches. The other two models were essentially large containers with dividers inside and either a simple lift-off lid or latches that snapped shut. We included lunchboxes made of both metal and plastic, and because we wanted a product that anyone could use, we excluded those designed specifically for kids.
To test the lunchboxes, we measured capacity—we didn't want to be left hungry after lunch—and checked whether any leaked. We filled them with both smelly and stain-inducing foods to see if any models retained odors or stained easily, and we opened and closed them multiple times to determine whether doing so was easy or not. We also dropped each model a few times, repeatedly washed each one, and asked colleagues to use the boxes for one week to find out how they fared in the real world with real lunches.
All the bento-style lunchboxes were easy to clean and satisfactorily resistant to stains and odors. They all also held up well to repeated dishwasher cycles. But there were key differences in size, ease of use, and leakage that determined our rankings.
Size: We Liked a Larger Capacity and Deeper Containers
The models in our lineup ranged in capacity from 3⅔ to 8 cups. Inside each one, we attempted to fit a reasonably sized lunch that, in the tradition of these containers, included a variety of foods: a peanut butter and jelly sandwich, five broccoli florets, six baby carrots, 10 grapes, 12 almonds, and two dark chocolate squares. We also shook them with the lunch inside to see if the food shifted substantially.
All the lunchboxes accommodated a peanut butter and jelly sandwich with no squishing necessary—although some did so with nary a millimeter to spare. But three containers were too small to fit all the additional snacks. The smallest model forced us to leave out the most food: Nearly all the grapes, a carrot, and a couple of broccoli florets. Another model also forced us to skimp on our fruit and vegetables, and a third didn't have room for the two dark chocolate squares. The latter stacked vertically, and the upper compartment's bottom nested into the shallow lower compartment by ¼ inch, depriving us of valuable space. The remaining three boxes fit the entire lunch, with our favorite being the largest. Its 8-cup capacity made it easy to fit foods of all shapes and sizes.
But a good lunchbox isn't just for transporting food. When our panel of testers put the containers to use with real lunches, they found that some were more difficult to eat from. Compartments that were too shallow, only 1⅛ to 1⅝ inches deep, sometimes made it difficult to stir and scoop food without spilling. The highest-ranked boxes were approximately 2 inches high, and our favorite was slightly taller, at 2¼ inches.
Ease of Use: Versatility, Lids, and Material Mattered
Most models had a fixed configuration, but two gave us the option to use compartments separately. One such lunchbox had stacking top and bottom containers with a combined 5-cup capacity. But if we wanted to pack a snack instead of a full meal, we could also use the upper container on its own.
Our favorite lunchbox was even more versatile. It had two compartments, each with a roomy 4-cup capacity; they could be held together with a large elastic band or used separately and bound with a smaller elastic band (which was included). One tester, who preferred to use the compartments separately, said the versatility allowed her to prep two meals at once.
We also examined how easy it was to open and close all the containers, and two models had issues. One had a lid that appeared closed when it wasn't—it required a forceful push to completely shut. The top compartment also didn't easily stack atop the bottom one, leaving us wondering whether it was locked into place or not. The other problematic model had a lid that didn't always sit flush with the container itself, so we had to inspect it carefully before latching the handles shut. The remaining three models were much easier to operate.
Finally, four models were plastic, but two were metal and as such could not go in the microwave. This wasn't a deal breaker, but we preferred having the option of reheating our food without transferring it to another container.
Only One Lunchbox Was Truly Leakproof
According to product descriptions, three models were not designed to be leakproof. (And in fairness, traditional bento boxes typically didn't contain liquids.) But because it's an important factor—lunch containers get jostled in bags and on commutes, and we don't want anything to spill—we tested to see if any of the containers were leakproof.
First, we added 4 ounces of water to each container and rotated them in all directions. All except one leaked. Then we tested again, this time with a handful of spring mix salad topped with a generous ¼ cup of our Make-Ahead Vinaigrette. We rotated the boxes, and only one model leaked. However, another model had interior dividers that didn't sit flush with the bottom of the container, so while salad dressing didn't actually leak out of that container, it did sneak into other compartments—and no one wants a dressing-soaked sandwich.
Our favorite model was fully leakproof—no water or salad dressing escaped—thanks to the airtight lids on each of its two stackable containers. And while we sometimes had to pry the lids off, we'd much rather spend extra effort opening a container than cleaning its contents out of our bag.
Our Favorite Bento-Style Lunchbox
While aesthetics certainly play a role in one's lunch container selection, based on function alone we liked the Monbento MB Square—Litchi best. It gave us plenty of room for food, with an 8-cup capacity and deep containers, and it was the only model that was truly leakproof. Its two 4-cup compartments could also be used together or individually, giving us a versatile lunchbox that could accommodate all appetites. And if pink doesn't suit your taste, don't worry; it comes in a variety of colors, including black, gray, and blue.
We purchased six bento-style lunchboxes, all under $40. We tested capacity by seeing if a lunch comprising foods of varying shapes and sizes (a peanut butter and jelly sandwich, five broccoli florets, six baby carrots, 10 grapes, 12 almonds, and two dark chocolate squares) could fit in each one. We also gauged capacity by filling each model with water to determine volume. To see if boxes leaked, we filled each one with 4 ounces of water and rotated it in all directions; we again rotated boxes after filling each one with 15 grams of spring mix salad topped with ¼ cup of our Make-Ahead Vinaigrette dressing. We filled each box with one sardine packed in tomato sauce, 1 teaspoon of minced garlic in 1 teaspoon of olive oil, 1 teaspoon of ground turmeric, and 55 grams of blueberries (partially crushed) to test staining, odor retention, and ease of cleaning. We dropped each box off the counter three times and washed each one 20 times to test durability. We disassembled and reassembled all boxes three times to see which were easiest to open and close, and we asked three additional users to do the same. We also assigned each lunchbox an owner for one week.
Size: We gave higher ratings to containers that had larger capacities and could hold the entire test lunch as well as users' work lunches and that had deeper compartments, which made it easier to stir food and eat from the containers.
Ease of Use: We disassembled and reassembled each model multiple times and asked a volunteer to use each one for a week. Containers that were easy to open and close and whose compartments could be used together or separately to accommodate meals of different sizes rated highest.
Leaks: We tested whether each lunchbox was leakproof by filling it with water as well as salad and vinaigrette and rotating it in all directions. We gave highest marks to containers that remained leak-free in both tests.
Durability: We dropped each box off the counter three times and washed each one 20 times. Those that emerged from testing without damage rated highest.