Onigiri (おにぎり), or sometimes called Omusubi (おむすび), are Japanese rice balls. They are what I call the magical food of the Japanese. Tender, toothsome rice made portable, they are the classic comfort food for picnics (especially during the sakura viewing), bento lunch boxes, quick grab-and-go snacks, hiking trips, movie snacks, etc.
Growing up in Japan, I have the fondest memories of helping my mom shape freshly cooked rice into triangles and pack them neatly into my bento boxes before running off to school. 
What is Onigiri (Omusubi)
Onigiri (おにぎり) are Japanese rice balls made of steamed rice that have been compressed into a triangular, ball, or cylinder shape and are usually wrapped in nori seaweed sheet. They can be flavored lightly with just salt or filled with a variety of fillings.
Onigiri – Omusubi – Nigirimeshi
The word “onigiri” is more commonly used throughout Japan, but it’s also known as nigirimeshi (握り飯) or omusubi (おむすび).
Is Onigiri Sushi?
For the uninitiated, onigiri are sometimes misunderstood as a type of sushi but they are not.
One of the key differences between onigiri and sushi is that onigiri starts from a base of plain steamed rice, while sushi is made of steamed rice seasoned with vinegar, salt, and sugar.
When to Eat Onigiri
Adored by all ages, onigiri prove their importance and popularity in Japanese everyday lives. We make the rice balls for school and work lunches, and for many outdoor activities and events.
In some ways, they are the Japanese idea of energy bars. We snack on onigiri when we need a quick boost of energy and sustenance.
Where to Get Onigiri
Outside of the home, you can literally find the rice balls everywhere: konbini convenience stores, airports, cute cafes, and specialty stores.
Brief History and Its Role in Japanese Culture
Deemed as the very first traveling food, onigiri were invented before the existence of refrigeration as a means to preserve fresh rice longer so it can be brought along to feed travelers, samurai, or soldiers on the road, or farmers in the farm fields.
The method was to fill the rice with a salty or sour ingredient as natural preservatives and lightly compact them into portable food that can be carried along and eaten with hands. To keep the rice safe, salt was first used in making the onigiri.
Today you can find these rice balls in so many varieties and forms, but the basics of making onigiri remain the same.
If you’re an anime or manga (Japanese comics) fan, you have most likely seen the onigiri show up in many storylines of these cultural outputs. The most memorable appearance has to be in a scene in Spirited Away, where a boy named Haku offered Chihiro, the main character, some onigiri in the hope of comforting her. As the young girl took a bite of the rice ball, tears started rolling down her cheeks. It tells the powerful connection between food and home and the emotions involved. As you can see, onigiri means a lot to the Japanese.
Onigiri Ingredients
For the most basic and comforting onigiri, you’ll need only 2 ingredients. That’s right! All you need is cooked rice and good quality nori seaweed.
- Japanese Short-Grain Rice – Commonly labeled as sushi rice outside of Japan, Japanese short-grain rice is the rice that we use in most Japanese cooking. It gives you the perfect chewy, tender, and slightly sticky texture. I personally recommend Koshihikari. Please do not substitute it with jasmine or any other types of rice as they will fall apart. Wish to learn more about Japanese rice? Read this post.
- Nori Seaweed – This is the same seaweed wrapper that we use to wrap sushi. You can find it at Japanese/Asian grocers, well-stocked grocery stores, or online.
- Optional Fillings – We’ll discuss them below.
Onigiri Filling
Yes, you can fill onigiri with whatever your heart desires, but I’ll share with you some of the most common fillings for onigiri in Japan.
- shake [pronounced as sha-keh] (salted salmon)
- umeboshi (Japanese pickled plum)
- okaka (bonito flakes moistened with soy sauce)
- kombu (simmered kombu seaweed)
- tuna mayo (canned tuna with Japanese mayonnaise)
- tarako (salted cod roe)
- furikake (rice seasonings to sprinkle all over)
Now if you are ready to get creative, look no further than your dinner leftovers. I’ve used my leftovers from Chicken Karaage and Shrimp Tempura to fill my onigiri. Instead of plain steamed rice, you can also use Takikomi Gohan (mixed rice) or Corn Rice.
Onigiri Shapes and Variations
You can make many different shapes of onigiri, and the most common ones are:
- Triangular
- Cylindrical (shape of rice bale)
- Round/circular
- Cylindrical
- Creative – Some home cooks even take their onigiri to another high fashion level by shaping the rice balls into so many cute animals or character-based shapes!
We also enjoy onigiri in these popular variations:
- Onigirazu (Rice Sandwich)
- Yaki Onigiri (Grilled Rice Balls)
Nori Wrapping
There are different ways to wrap the nori around the rice balls. You can cut a sheet of nori into thin strips and wrap the nori around the cylindrical or triangular rice ball shape (this is more like a decoration).
You can also cut the nori sheet in thirds and wrap the rice ball with the nori.
Some prefer to wrap the rice balls when they are warm so the nori will stick to the rice (but it will be soggy/moist) but most people prefer to keep the nori as crisp as possible.
You can buy this onigiri plastic wrapper that allows you to keep the nori crispy until you’re ready to eat (similar to Japanese convenience store-style onigiri).
5 Tips for Making Perfect Onigiri
1. Use freshly cooked rice
I strongly recommend using freshly cooked rice instead of older rice when you make onigiri. Transfer the freshly cooked rice to a baking sheet or sushi oke (hangiri). Let cool just slightly: The rice should be warm when you make onigiri. Always keep the rice and rice balls covered with a plastic or a damp towel so the rice will not dry out quickly.
2. Wet and salt your hands
It’s important to wet your hands with water to prevent the rice from sticking. Prepare a bowl of water next to your working station. Salt both your hands and rub to spread all around. Salting helps to flavor and to preserve the onigiri for a longer time.
3. Give just enough pressure
Your hands should be just firm enough when pressing the onigiri so the rice doesn’t fall apart when you shape them. You don’t want to squeeze the rice too tight. You rotate the rice balls every time you give gentle pressure. After rotating 3-5 times, the rice ball should be in good shape.
4. Identify your rice ball with a filling
If you add a filling, make sure to place a small amount of the filling on the rice ball (such as on a tip of the triangle shape) so you can identify which filling is inside.
5. Wrap the nori before you eat
Wrap the nori seaweed before you serve. Some onigiri shops sell rice balls that are already wrapped in nori so it’s not crispy. Sometimes nori is packed separately and you get to enjoy the crispy nori. We have both styles, so it’s up to your preference.
If you serve onigiri at a party, you can quickly wrap them right before you serve, or serve the rice balls and nori separately and make it optional.
Frequent Asked Questions
Why does my nori get soggy and wet?
Nori gets soggy as soon as it absorbs moisture. If you prefer crispy nori for your onigiri, I recommend wrapping the nori right before you eat. Make sure the nori is kept in a resealable bag to avoid getting stale.
Why does my nori get gummy?
I recommend getting better quality nori, preferably imported from Japan. It’s very unfortunate but nori available in grocery stores here is not flavorful and the texture becomes gummy when wet/moist. I always get imported nori from Japan (I usually pick the most expensive nori at Nijiya Market) and it’s pretty good. We can get better quality nori in Japan at a decent price, but not outside of Japan yet.
Do I have to make onigiri right before I pack for lunch?
If you want to make onigiri for lunch the next day but don’t want to wake up early, here’s my tip. You can wrap the finished onigiri (in plastic wrap) with a thick kitchen towel. The kitchen towel protects the rice balls from being too cold in the refrigerator. Rice gets hard in the refrigerator but with this easy trick, your onigiri will be cool enough to stay safe.
Do you serve onigiri cold?
You can enjoy onigiri warm or at room temperature, so they’re perfect in your lunchbox or as a portable snack on the go. You can even plate them up as a tasty appetizer!
Do you think I can involve my children to make rice balls?
Yes! The best part about making onigiri at home is you can always engage your little ones as their ‘craft day in the kitchen.’ Make it fun and enjoyable! You can use this onigiri mold to make it easier to create a triangle shape.
Like everything else, practice makes perfect when comes to making onigiri. For a visual guide, you can watch my video and see the step-by-step instructions below.
More Onigiri Recipes You’ll Enjoy
- Tenmusu (Shrimp Tempura Rice Balls)
- Salmon Onigiri
- Cherry Blossom Onigiri
- Ume Miso & Shiso Onigiri
- Plum Rice Balls
INGREDIENTS
For the Steamed Rice
2 cups uncooked Japanese short-grain rice2½ cups water
For the Onigiri
kosher salt (Diamond Crystal; use half for table salt)4 sheets nori (dried laver seaweed)
Japanese Salted Salmon (homemade or store bought) (recipe follows; see my Japanese Salted Salmon recipe post for more details)
okaka (recipe follows)
tuna mayo (recipe follows)
3 umeboshi (Japanese pickled plum)
seasoned kombu (prepared)
toasted white and black sesame seeds (to garnish)
For the Japanese Salted Salmon (Quick Version)
1 fillet salmonkosher salt (Diamond Crystal; use half for table salt)
For the Okaka
⅔ cup katsuobushi (dried bonito flakes)2 Tbsp soy sauce
For the Tuna Mayo
½ (5-ounce) can albacore tuna (preferably packed in olive oil) (2.5 oz, 70 g)2 Tbsp Japanese mayonnaise
½ Tbsp soy sauce
INSTRUCTIONS
To Prepare the Steamed Rice
1.You can also cook short-grain rice with a rice cooker, Instant Pot, or donabe.2.Put the rice in a large bowl and gently wash the rice in a circular motion and discard the water. Repeat this process about 3-4 times.
3.Let the rice soak in water for 30 minutes. Transfer the rice to a sieve and drain it completely for at least 15 minutes.
4.Combine the rice and measured water in a heavy-bottomed pot. I recommend a heavy-bottomed pot with a tight-fitting lid as it is thicker at the base so it maintains and distributes heat better. Cover the pot with the lid and bring it to a boil over medium heat.
5.Once the water is boiling, turn the heat to the lowest setting and continue to cook covered for 12 to 13 minutes, or until the water is completely absorbed. At the 12- to 13-minute mark, take a quick peek; if there is any water left, close the lid and continue cooking for another minute or so.
6.Remove the pot (with the lid on) from the heat and let it steam for another 10 minutes. Then, remove the lid and transfer the rice to a large plate or baking sheet lined with parchment paper (I use a sushi oke). Fluff the rice with a rice paddle. Let the hot rice cool until it’s warm and you can hold the rice without burning your hands. However, do not let the rice completely cool down.
To Prepare the Onigiri Fillings
1.While the rice is draining and soaking (45 minutes), prepare the onigiri fillings.2.Japanese Salted Salmon Filling: Sprinkle kosher salt on both sides of the salmon fillet. Bake at 425ºF (218ºC) in a toaster oven or standard oven for 10-20 minutes. Japanese salted salmon is cooked until well done (you want it dry and flaky).
3.Break the cooked salmon into flakes and set aside.
4.Umeboshi Filling: Place the umeboshi (Japanese pickled plums) on a 10-inch by 10-inch (25 cm x 25 cm) sheet of plastic wrap. Fold the plastic wrap in half over the umeboshi and squeeze the seed out from each umeboshi. Discard the seeds and put the umeboshi flesh on a small plate.
5.Okaka Filling: Put the katsuobushi (dried bonito flakes) in a bowl and add the soy sauce. Mix to combine. The katsuobushi should be moistened but not drenched in soy sauce.
6.Tuna Mayo Filling: Put the drained canned tuna in a bowl and add the Japanese mayonnaise and soy sauce. Mix to combine.
7.Seasoned Kombu Filling: Put the prepared seasoned kombu in a bowl for easy access later.
To Make the Onigiri
1.See the alternative method below if you plan on serving the onigiri later or packing for lunch. Cut the nori sheets into thirds.
2.First, wet both of your hands with water to prevent the rice from sticking to your hands.
3.Then put some salt in your hand and rub to spread it on your palms. How much salt? I dip three fingertips in kosher salt as pictured below. If you are using table salt, use half the amount as it’s saltier than kosher salt.
4.Scoop a handful of warm rice (about ⅓ cup) into one hand. Create a small well (indentation) in the center of the rice. Put one kind of filling (about 1-2 tsp) inside. Then mold the rice with your hands around the well to cover your filling completely.
5.Gently press the rice around the filling to form the rice into a triangle. I use three fingers (thumb, index finger, and middle finger) to make a triangle corner. Your hands should be just firm enough so the onigiri doesn't fall apart. You don't want to squeeze the rice too tightly.
6.Wrap the onigiri with a piece of nori seaweed. If you like the crispy nori, wrap it with nori right before consuming the onigiri. Make sure to keep the nori in an airtight container or bag so it will not get stale.
7.Place a little bit of each filling on the tip of the onigiri so you can identify which filling is inside.
Alternative Method of Making the Onigiri
1.Use this method when you are serving onigiri for later or packing for lunch. Place a piece of plastic wrap in a rice bowl (or any small bowl) and put the rice on top. Sprinkle some kosher salt (remember, salt is used here to preserve the rice for a long time). If you like to add a filling, create a small well (indentation) in the center of the rice. Put one kind of filling (about 1-2 tsp) inside.
2.Gather the corners of the plastic wrap and twist the plastic a few times to tighten it around the rice.
3.Form the rice into a triangle shape in the same manner that I described above.
To Serve
1.Enjoy onigiri warm or at room temperature.
To Store
1.If you like to pack for your lunch, keep it cool and consume it within 6 hours. Onigiri (or any rice dish) gets hard when you refrigerate it. The cold air makes the rice dry and hard, which is perfect for fried rice. I don't recommend making onigiri ahead of time. But if you really need to, my trick is to wrap the onigiri with thick kitchen towels and store it in the fridge. The onigiri will be cool and safe but should not get cold.2.If your onigiri has dried out a bit, you can grill it in a frying pan and baste it with soy sauce to make yaki onigiri.
