Japanese Plate Sizes: Sun to cm Conversion Chart

Trying to choose Japanese tableware, have you ever been thrown by labels like "5-sun plate" or "7-sun plate"? The actual size is hard to picture, and it is not clear how it compares with what you already own.

Japanese tableware states size in a unit called sun. Understand the sun, and choosing gets far easier.

This article covers everything worth knowing when choosing Japanese tableware — from conversion tables, through the names for the parts of a piece, to the specialist vocabulary.

What the Japanese Size Unit "Sun" Is

Japanese tableware states size in sun. One sun is about 3.03cm, said to derive from the width of a thumb. One shaku (about 30.3cm) is said to be based on the length from elbow to wrist (or fingertip) — units taken from the body itself (accounts vary).

That is why the sense of scale in Japanese tableware shows itself less as a number than as how well a piece settles into the hand.

Sun, Centimetre and Inch Conversion Table

So how many centimetres is a sun, exactly? Check the table below.

Japanese and Western Sizes Compared

Set Western flat plates (in inches) beside Japanese ware (in sun) and the scales feel surprisingly close. That is because one inch (about 2.54cm) and one sun (about 3.03cm) both developed from the size of a human hand and the sense of the body.

Compare them directly and the 10-inch (about 25.4cm) dinner plate used for Western food is close to a Japanese 8-sun plate (about 24cm). They do not match exactly, but since both take an easily handled scale as their basis, combining Japanese and Western ware rarely feels wrong.

That is why the style of combining Japanese and Western ware freely has spread on the contemporary table.

Points for Buying Online

When choosing Japanese tableware online, use the conversion table above and compare with what you have. Measuring 4 sun (about 12cm), 5 sun (about 15cm) and 7 sun (about 21cm) with a ruler or tape makes them far easier to picture.

You can also infer thickness and weight from photographs. A thicker rim reads as substantial and holds heat better; a thin one is light and delicate. The construction of the base tells you something about stability and weight too. Enlarge the photographs and look at the detail. → Buying Japanese Pottery Online: What to Check First

Sizes and Types of Japanese Tableware

With the conversions clear, the next question is how to use them. Here we look at choosing Japanese tableware both by the names given to sizes and by type of form and function.

The Names for Each Size, and How They Are Used

Japanese tableware has a name for each size. Knowing what each is for makes choosing smooth.

• Mamezara (3 sun, approx. 9cm)　Generally defined as 3 sun or under. Once called teshiozara, it held the salt used to purify a meal tray. Today it holds condiments and pickles, serves as a dish for soy sauce, and works for nuts or chocolate with tea. Setting out several in different designs adds colour and playfulness to a table.
• Small plate (4 sun, approx. 12cm)　The easiest size to use as a side plate. Right for fruit, dressed vegetables and shared salad, and just as good for yoghurt or jam at breakfast. Gathering one per person makes it earn its place daily.
• Medium plate (5 sun, approx. 15cm)　The core medium size, working as a cake plate and an all-purpose side plate. Right for one person's side dish, and versatile enough for salads, simmered dishes and much else.

• Bread plate (6 sun, approx. 18cm)　Ideal for toast or a plate of salad. Classed as a medium plate but a little larger, which makes it useful. It works as a breakfast one-plate too, and earns its place whenever 5 sun is slightly small and 7 sun too large.
• Main plate (7 sun, approx. 21cm)　Ideal for a main dish, and right for pasta. A little smaller than a typical Western dinner plate (about 25–27cm), it settles well onto a table mixing Japanese and Western food.
• Serving plate (8 sun, approx. 24cm)　Works as a large plate for a one-plate meal or a family braise. Suited to dishes shared between several people — fried chicken, roasted vegetables, an arrangement of sashimi — and it earns its place when hosting.

• Shaku plate (approx. 30cm)　A large plate that works for parties. It presents hors d'oeuvres or an arrangement of fruit splendidly when hosting. Less an everyday piece than one to keep for special days.
• Shakuhachi plate (approx. 54cm)　Overwhelming in presence, used as a display plate in venues and at special banquets. Its role is less practical than decorative — some hang it on a wall as an interior piece. It is rarely used in an ordinary home, and even the name is unfamiliar.

Types by Form and Function

Beyond size, knowing the classification by form and function widens the range of what you can choose.

Rice Bowl (Meshiwan) and Soup Bowl (Shiruwan)

The rice bowl is the piece rice is served in, mostly made in earthenware or porcelain. The soup bowl, meanwhile, is the wooden (lacquer) bowl for miso soup and clear soup. Both are special pieces used every day on the Japanese table, ware that is "held in the hand while eating."

The difference is not only material. A rice bowl needs a moderate depth so rice can be gathered easily, and a stable foot ring; the warmth of earthenware is its character.

A soup bowl, on the other hand, touches the lips directly, so the feel of the rim matters, and the insulation of lacquer protects the hand from hot soup. Layering natural urushi is a technique used in Japan for thousands of years, a traditional skill precious worldwide.

For the rice bowl size that suits you, the ring made by your thumb and middle finger is the guide. Standard sizes are generally 4 sun (about 12cm) for men and 3.8 sun (about 11.5cm) for women, though with today's varied eating there is no need to hold to that.

The standard soup bowl is 11–12cm across and about 6cm high. For a hearty pork soup, choosing 12cm or larger lets it double as a bowl for small noodles or a rice bowl dish. → How to Choose a Japanese Rice Bowl (Chawan)

Bowls: Shallow, Deep and Large

Hachi is the collective term for ware with depth. How you use them changes with that depth. A deep bowl suits dishes with liquid, such as simmered food or stew; a shallow bowl makes food you want to show — salads, dressed vegetables — look its best. Ramen bowls, rice bowl dishes, salad bowls: useful ware for Japanese and Western food alike.

Mukozuke

Mukozuke takes its name from being placed on the far side of the tray, and its role is to set off sashimi and dressed dishes. Unlike a flat plate, it is characterised by a slight rise at the sides.

Adding a mukozuke among flat plates gives the table a pleasant difference in height, and a rhythm.

Choko and Soba Choko

A choko is a small cup around 7.5–9cm across (2.5–3 sun). Originally ware for drinking sake, it came to be used as the soba-choko that holds noodle dipping sauce.

That size is said to be based on the inner width of the palm when a hand closes naturally. This ease of holding is the choko's characteristic. Beyond drinks it serves as a small bowl for side dishes or dessert — highly free ware that answers the user's imagination.

Kinds of sake ware are covered in more detail below, so do use it as a reference.

• Ochoko, Guinomi, Sakazuki: Japanese Sake Cups Compared

The Names for the Parts of a Piece

With sizes and types clear, look next at how a piece itself is built. Knowing the names for its parts is a clue to where a maker put their soul, and what movement of yours they imagined.

Kouen: The Rim

The edge of a piece is called the kouen. This is where lips touch directly. It governs both the practical matter of how cleanly liquid leaves the piece, and how good it feels against the mouth.

A rim turned outward, hazori, meets the mouth well and lets a drink flow in smoothly. A rim curving inward, by contrast, is a device for holding the aroma in. Because the degree of that turn changes how flavour is felt, it is one of the parts a maker attends to most closely.

Do and Koshi: Body and Waist

The side of a piece is the do, and the swelling near the base the koshi. Where the maker's finger marks or spatula traces remain here, you feel the movement in the clay directly. How far the waist swells expresses either strength or delicacy.

Mikomi: The Inner Base

The inside base of a piece, the ground behind whatever is served, is called the mikomi. It reveals itself little by little as the food is eaten. Makers set devices there to hold your interest to the last mouthful — a deliberate pool of glaze, or painting.

Kodai: The Foot Ring

The kodai is the ring beneath a piece, like a pedestal. It has the function of letting you hold the piece when it holds hot soup, and the role of raising it a step on the tray, giving it dignity.

"People who love ware turn it over," as the saying goes — the foot ring is an important point of appreciation. A maker's particularity is concentrated in its shape.

When you look at a foot ring, do pay attention to the cutting. From the traces left by a bamboo spatula you can feel the momentum of the maker's hand.

Beside or inside the foot ring, the maker's signature or seal is cut. Finding a small stamp or a swiftly written signature brings the maker close.

Tatamitsuki: The Standing Surface

The underside of the foot ring, the part that touches the table directly. Finished carelessly, it scratches a table. Conscientious makers and kilns polish it carefully. When a piece arrives, run a finger over it and check for roughness — an important point. If it concerns you, speak to the shop.

Vocabulary Worth Knowing

Once you know the parts, the next thing you notice is the keshiki. Have you ever wondered "what is this black speck?" or "is this crack all right?" Japanese ware, earthenware especially, holds individual variation: no two pieces are the same.

During firing, flame, ash and the components of clay react and produce unforeseen change. Calling this not a defect but a "keshiki," a landscape, and cherishing it, is a distinctly Japanese sense of beauty.

Here we explain the vocabulary worth knowing to enjoy Japanese ware further.

Keshiki

In the world of Japanese ware, the word keshiki is used. It means the character that emerges on a fired surface when changes belonging to that piece alone overlap — the work of flame and ash in the kiln, the shift and flow of glaze colour.

Regarding even a small scratch or a coffee stain as part of a piece's history, and cherishing imperfection along with everything else, is what the spirit of wabi-sabi means.

• Keshiki: How to Read the 'Landscape' on a Pot

Yohen

Yohen means the glaze colour changing according to how flame strikes inside the kiln. It is also called hi-gawari.

Even with the same glaze, one piece comes out blue and another red-purple: flame and ash produce colour shifts no one foresaw.

Kannyu and Nyu

Kannyu, crazing, means the fine cracks that enter the glaze layer, born of the difference in shrinkage between the body (clay) and the glaze (glass). It is not breakage; crazing that catches light and glitters enriches a piece's expression. There is even a technique of running ink into it to bring the pattern out deliberately.

A crack reaching the body itself, meanwhile, is called nyu. In the antique world, moisture seeping from such a crack and appearing on the surface as a stain is called amamori, "rain leak," and is sometimes prized as a weathered charm. As practical tableware, though, it needs care for hygiene and strength.

• Crazing (Kannyu): Cracks in Glaze That Aren't Damage

Teppun: Iron Specks

Teppun is iron in the clay appearing on the surface as black specks through firing. On pure white porcelain it is sometimes unwelcome, but on earthenware these black points become a charm point, giving an organic warmth.

Gohonde

Gohonde is the phenomenon of faint red or pink spots appearing. It has a soft, gentle atmosphere, welcomed especially on matcha bowls and yunomi. A keshiki that makes you feel the piece's own body heat, as though it were flushed.

Meato: Stacking Marks

Meato means the marks left when pieces are stacked for firing. They remain as traces of the firing, adding a character as though the piece were already well used.

Pinholes

A pinhole is a tiny hole, as though pricked by a needle. They arise when air enters as glaze is applied, or when a bubble escapes during firing. Sometimes they read as small points; sometimes they scatter across a surface and make a distinctive expression.

Yudamari: Pooled Glaze

Yudamari means a place where glaze has pooled thickly. It arises readily at the rim, around the foot ring and at the base of the mikomi, showing a deeper colour or a glassy quality. The name comes from the way glaze flows and gathers.

The Pleasure of "Growing" Japanese Ware

Among the keshiki we have seen, some change through use. Crazing and rain-leak especially shift their expression with time. Japanese ware holds a distinctive aesthetic of enjoying that change: nurturing a piece.

As you use it at daily meals, wash it and care for it repeatedly, a piece changes little by little. Enjoying that change not as deterioration but as the process of a piece deepening in character is a way of thinking particular to Japanese ware.

Crazing and Change Over Years

The pleasure of "growing" appears most in crazing — the fine pattern of cracks that enters the glaze surface during cooling after firing.

Transparent and inconspicuous at first, these cracks slowly take in the oil of food and the tannin of tea over long years. A geometric brown line rises on a white piece, and eventually the whole takes on a soft amber.

This is called "the crazing staining." Just as leather takes on gloss as it settles into a hand, the life of the user is inscribed as the piece's own pattern.

There is more to the appeal of nurturing Japanese ware than this article can hold, so the article below covers it in detail. Do use it as a reference.

• Pottery That 'Grows': How Ceramics Change With Use

The Deep Character of "Amamori"

On well-used pieces, a keshiki called amamori, rain leak, sometimes appears. It is the state where moisture that entered the body seeps to the surface and makes a faint stain like the trace of rain.

Practically it is close to soiling or leaking, a state you would avoid in everyday ware. Yet the world of tea, and those who love ware, found in this stain the charm of rain soaking into an old earthen wall, and cherished it under that poetic name.

Seeing even an accidental stain as the blessing of rain falling from the sky. The spirit of wabi-sabi — finding beauty in the imperfect — lives here.

Choose Ware Alive With a Japanese Sense of the Body, and Grow Its Keshiki

Knowing the names for the parts of Japanese ware, and understanding its traditional unit of size, makes choosing far more enjoyable. Used daily, a piece shifts its expression little by little and grows into a piece that is yours alone. Ware that carries "the pleasure of growing" becomes ware you can use for a long time — and one day, ware you want to pass to the next generation.

Even the "○ sun" that felt difficult until now should come to feel closer and more lovable, once you know it is a warm unit born from the size of our bodies and how well something settles into a palm. The neat fit of a 4-sun side plate; the breadth of a 7-sun main plate that suits Japanese and Western food alike. Ruler in hand, comparing with what you own and imagining "the next piece" online, is itself a pleasant process particular to Japanese ware.

Knowing the names of parts and the vocabulary of keshiki is not merely accumulating knowledge. It is a passport to conversation with a piece — to feeling the movement of the hand that cut the foot ring, and standing at the moment flame and clay worked their miracle inside the kiln.

The brand-new state you buy is not the completion of a piece but the starting line. Serving food at daily meals, washing carefully, letting it air. Through that unremarkable routine, a story that belongs only to you — stained crazing, a rain leak — is inscribed into the piece. Do bring ware packed with Japanese wisdom and a sense of beauty onto your table.

Related Articles and Guides

More on the Culture and History of Japanese Ceramics

• A Short History of Japanese Ceramics, Jomon to Now
• Reading Wabi-Sabi in a Single Bowl
• Wabi-Sabi in Ceramics: What It Actually Means
• Pottery That 'Grows': How Ceramics Change With Use
• Ichigo Ichie: Why No Two Handmade Pieces Repeat
• Keshiki: How to Read the 'Landscape' on a Pot

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• Japanese Pottery by Region: A Buyer's Map
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• Why Japanese Pottery Is Worth Buying (and Keeping)
• Stoneware vs Porcelain: How to Tell Them Apart
• Earthenware, Stoneware, Porcelain: The Real Differences
• Ochoko, Guinomi, Sakazuki: Japanese Sake Cups Compared
• How to Choose a Japanese Rice Bowl (Chawan)

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