Japanese Pottery Sizes: A Complete Guide to “Sun(寸)”
Have you ever browsed Japanese pottery online and been puzzled by listings marked “5-sun plate” or “7-sun plate”? The actual size is hard to picture, and even harder to compare with what you already own.
Japanese tableware uses sun (寸) as its unit of measurement. Once you understand sun, choosing Japanese ceramics becomes far more intuitive.
This article covers everything you need to know when selecting japanese pottery: a full size conversion table, a guide to plate and bowl types by name, the names of a piece’s individual parts, and the key terminology that helps you read what a potter has left on the surface.
What Is Sun? The Unit Behind Japanese Pottery Sizes
Japanese tableware is measured in sun (寸). One sun is approximately 3.03 cm, said to derive from the width of a thumb. One shaku (尺, approximately 30.3 cm) was based on the distance from the elbow to the wrist or fingertips — measurements rooted in the human body. (Exact origins vary by account.)
Because these units emerged from the body’s own proportions, the size of japanese ceramics tends to feel right in the hand in a way that pure numbers cannot fully capture.
Sun, Centimetre, and Inch Conversion Table
How many centimetres is each sun size? The table below shows the full range, with common uses for each.
| Size | Centimetres | Inches | Common Use |
|---|---|---|---|
| 3-sun (mamezara) | approx. 9 cm | approx. 3.5 in | Condiments, single-bite sweets |
| 4-sun (small plate) | approx. 12 cm | approx. 4.7 in | Sharing plate, fruit |
| 5-sun (medium plate) | approx. 15 cm | approx. 5.9 in | Cake plate, sharing plate |
| 6-sun (side plate) | approx. 18 cm | approx. 7.1 in | Grilled fish, toast |
| 7-sun (main dish plate) | approx. 21 cm | approx. 8.3 in | Main courses, pasta |
| 8-sun (serving platter) | approx. 24 cm | approx. 9.4 in | One-plate meals, shared dishes |
| Shaku plate (large platter) | approx. 30 cm | approx. 11.8 in | Party serving |
| Shakuhachi plate (extra-large) | approx. 54 cm | approx. 21 in | Display piece, formal banquets |
Comparing Japanese and Western Tableware Sizes
When you place a Japanese piece (measured in sun) next to a Western plate (measured in inches), the sizes are often surprisingly close. This is because both units grew from the same source: the human hand and body. One inch is approximately 2.54 cm; one sun is approximately 3.03 cm — different in precise value, but both calibrated to how things feel in use.
A Western 10-inch dinner plate (approximately 25.4 cm) is close in size to a Japanese 8-sun plate (approximately 24 cm). They are not identical, but both are built around comfortable, practical proportions — which is why mixing japanese tableware and Western tableware on the same table tends to feel natural rather than awkward.
| Function | Japanese (sun) | Western equivalent |
|---|---|---|
| Sharing / side plate | 4–5 sun (12–15 cm) | Bread plate (approx. 12–15 cm) |
| Side dish plate | 6 sun (approx. 18 cm) | Side plate (approx. 17 cm) |
| Main dish plate | 7 sun (approx. 21 cm) | Salad plate (approx. 20 cm) |
| Large shared plate | 8 sun (approx. 24 cm) | Smaller dinner plate (approx. 25 cm+) |
The ease of mixing the two traditions is one reason modern Japanese tables often blend japanese ceramics and Western tableware freely.
Tips for Buying Japanese Pottery Online
When shopping for japanese pottery online, use the conversion table above alongside pieces you already own. Measuring 12 cm, 15 cm, or 21 cm on a ruler gives you a much clearer sense of scale than numbers alone.
You can also read a piece’s weight and thickness from photographs. A thicker rim suggests a heavier, more heat-retaining piece with a solid presence; a thinner rim suggests something light and refined. The construction of the foot (the base ring of the piece) hints at stability and weight. Zoom in on details — they tell you more than the product description.
Japanese Pottery Sizes and Types
Now that the conversions are clear, the next step is knowing how each size is actually used. Here we look at japanese tableware both by the names given to each size and by the types defined by shape and function.
Size Names and How to Use Them
Japanese pottery has a traditional name for each size range. Knowing the purpose of each makes selecting pieces far more straightforward.
Mamezara — 3-Sun (approx. 9 cm)
Mamezara (豆皿, literally “bean dish”) are generally any plate 3 sun or smaller. Historically called teshio-zara (手塩皿, “hand-salt dish”), they were used to hold the small portion of salt placed at a meal setting as a purifying gesture. Today they serve condiments (yakumi) and pickles, as a soy sauce dish, or as a resting place for a single chocolate or nut alongside tea. A set of mamezara in different patterns arranged together brings colour and playfulness to the table — that variety is part of their appeal.
Small Plate (Kozara) — 4-Sun (approx. 12 cm)
The most versatile sharing plate size. Works equally well for fruit, dressed salads, morning yoghurt, or a small portion of jam. Easy to hold and pass, a set of four or five in matching or complementary designs covers the daily table almost completely.
Medium Plate (Nakazara) — 5-Sun (approx. 15 cm)
The core medium-plate size. Serves well as a cake plate or an all-purpose sharing plate, and is the right scale for a single serving of a side dish. Versatile across salads, simmered dishes, and many other preparations — one of the most useful sizes to own.
Side Plate (Pan-zara) — 6-Sun (approx. 18 cm)
Ideal for toast, a salad arrangement, or a light one-plate breakfast. Technically a medium plate but generously sized, this is the answer when 5 sun feels slightly small but 7 sun seems too large for the occasion.
Main Dish Plate — 7-Sun (approx. 21 cm)
The standard plate for a main course: the right size for pasta, grilled meat, or any substantial dish. Slightly smaller than a typical Western dinner plate (approximately 25–27 cm), it fits comfortably on a Japanese table while working equally well with Western food — a practical choice for mixed-style dining.
Serving Platter (Moritsara) — 8-Sun (approx. 24 cm)
A generous platter for one-plate meals or family-sized simmered dishes. Well suited for shared food: a pile of karaage, roasted vegetables, or a sashimi arrangement. Useful at the table for entertaining, where presentation matters.
Shaku Plate — approx. 30 cm
Large enough for a party spread: canapés, fruit arrangements, and festive presentations. Less for everyday use and more for special occasions, kept at the back of the cupboard and brought out when the table needs a centrepiece.
Shakuhachi Plate — approx. 54 cm
An imposing scale that commands attention: used as a display piece in restaurants, for formal banquet presentations, or as decorative wall art. Rarely found in private homes and rarely known by this name outside specialist circles.
Types by Shape and Function
Beyond size, understanding the categories defined by shape and use broadens your eye for japanese ceramics considerably.
Meshiwan (Rice Bowl) and Shiruwan (Soup Bowl)
Meshiwan (飯碗) is the bowl for rice — typically made in earthenware or porcelain. Shiruwan (汁椀) is the bowl for miso soup or suimono (clear broth), traditionally made in lacquered wood. Both are “picked up and eaten from” at the Japanese table, which makes them daily objects of a particular intimacy.
The two differ in more than material. A meshiwan needs a stable kōdai (foot ring) and enough depth to scoop rice comfortably; the warmth of earthenware suits it well. A shiruwan touches the lips directly, so the feel of the rim is important; the insulating properties of lacquered wood protect the hands from hot liquid. The traditional technique of layering natural urushi lacquer — used in Japan for thousands of years — is one of the world’s rare living craft traditions.
To find your ideal meshiwan size: form a circle with the thumbs and middle fingers of both hands — that circle is approximately right. The general standard is 4 sun (approx. 12 cm diameter) for men and 3.8 sun (approx. 11.5 cm) for women, though modern eating habits make these guidelines flexible.
Standard shiruwan dimensions are 11–12 cm in diameter and approximately 6 cm in height. For a chunky tonjiru (pork and vegetable miso soup), a bowl of 12 cm or more can double as a small udon or rice bowl as needed.
Hachi — Shallow, Deep, and Large Bowls
Hachi (鉢) is the general term for any bowl with significant depth. The depth determines the use: fukabachi (深鉢, deep bowl) for simmered dishes or stews with plenty of liquid; asabachi (浅鉢, shallow bowl) for salads and dressed preparations where the colours of the food should be visible. As a category, hachi crosses easily between japanese and Western food — ramen bowls, donburi bowls, and salad bowls all belong here.
Mukōzuke (Serving Dish)
The name mukōzuke (向付) comes from its position: placed on the far (mukō) side of the dining tray. It is typically used for sashimi or dressed preparations and has a slight upward curve to its sides, unlike a flat plate. The addition of mukōzuke to a table setting introduces a pleasant variation in height and rhythm among the pieces.
Choko (Small Cup) and Sobachoko (Soba Cup)
Choko (猪口) — also called ochoko — are small cups approximately 7.5–9 cm in diameter (2.5 to 3 sun). Originally used for sake, they came to be used as sobachoko (蕎麦猪口, soba dipping cups) as well. A sake cup in this size range is one of the most collectible forms in japanese ceramics, and ochoko are a perennial favourite among collectors for their scale, variety, and the way a beautiful glaze reads at close range.
The size of a choko is said to correspond to the inner diameter of the hand when the fingers are loosely closed — a measure of natural graspability. Beyond sake and soba dipping sauce, a choko serves as a small side bowl, a dessert cup, or a holder for a condiment: its freedom of use matches the imagination of whoever holds it.
Learn more about Sake ware, please read this too.
The Parts of a Japanese Ceramic Piece
Now that you know the sizes and types, it is worth looking closely at the construction of the pieces themselves. Knowing the names of a piece’s individual parts is a guide to where a potter has placed their care — and a way of understanding what they imagined in the hands of the person who would use it.
Kōen — The Rim
The rim (kōen, 口縁) is the edge of the piece, the part that makes direct contact with the lips. It governs both the practical flow of liquid and the feel of the piece against the mouth.
A rim that curves outward — hazori (端反り) — meets the lips softly and lets liquid flow cleanly. A rim that curves inward holds aroma inside. The precise angle of a rim changes how a dish tastes and how a drink feels — which is why potters give it serious attention.
Dō (Body) and Koshi (Lower Body)
The dō (胴) is the side of the piece; the koshi (腰) is the swelling near the base. Where the potter’s fingers or a wooden tool have left marks on the dō and koshi, the energy of the clay comes through directly. The way the koshi flares or tightens determines whether the piece reads as powerful or delicate.
Mikomi — The Inner Base
The mikomi (見込み) is the interior floor of the piece — the background against which food is served. As you eat, this surface gradually reveals itself. Potters sometimes pool glaze here intentionally (yū-damari, glaze pooling), or apply painted decoration, so that the last bite offers a final surprise. The mikomi is where a piece hides its quietest pleasures.
Kōdai — The Foot
The kōdai (高台) is the ring-shaped foot on the underside of the piece. It lifts the piece off the tray surface, makes hot bowls easier to hold, and gives the piece a sense of standing with quiet dignity. Connoisseurs say “a lover of japanese ceramics turns the piece over first” — the kōdai is one of the most telling places to look for a potter’s character.
| Foot type | Character |
|---|---|
| Wa-kōdai (ring foot, 輪高台) | The most common form — a clean doughnut ring. Stable and versatile. |
| Kittate-kōdai (straight-cut foot, 切立高台) | The foot rises vertically from the body. Modern, sharp, architectural. |
| Mikazuki-kōdai (crescent-moon foot, 三日月高台) | Part of the ring is removed to leave a crescent shape. Found in Hagi ware and other refined traditions — elegant and slightly playful. |
| Take-no-fushi-kōdai (bamboo-node foot, 竹の節高台) | The foot swells in the middle like a bamboo joint. Common on ceremonial tea bowls. |
When you examine a kōdai, look at the tool marks left by the trimming process — a bamboo spatula cutting through wet clay. The speed and confidence of those marks reveal the potter’s hand.
On the side and interior of the kōdai, you will often find the potter’s mei (銘) or shirushi (印): a seal, a carved signature, or a quick brushstroke. Finding it makes the maker feel present.
Tatamitsuki — The Contact Point
The tatamitsuki (畳付き) is the very bottom of the kōdai — the surface that rests directly on the table. If this is left rough, it will scratch surfaces. Conscientious potters and kiln studios grind and polish the tatamitsuki carefully. When a piece arrives, run a finger across it and check for roughness. If it feels sharp, contact the seller.
Key Terminology for Japanese Ceramics
Knowing the parts of a piece naturally leads to the question of its surface: “What is that black speck?” “Is this crack a problem?” In japanese ceramics — particularly in earthenware — no two pieces are ever identical. During firing, the interaction of flame, ash, and clay creates unpredictable changes. Rather than treating these as defects, Japanese ceramic culture embraces them as keshiki (景色, character / scenery) — a beautiful and uniquely Japanese aesthetic.
Here are the terms you need to appreciate japanese ceramics more fully.
Keshiki — Kiln Character
In the world of japanese ceramics, keshiki (景色, literally “scenery”) refers to the accumulated effect of everything the kiln has done to a piece: the movement and colour of glaze, the marks of flame and ash, the staining of years of use. A small nick, even a ring of coffee — these become part of a piece’s history, and are appreciated rather than mourned. This is the spirit of wabi-sabi: finding beauty in what is imperfect and impermanent.
Yōhen — Kiln Transformation
Yōhen (窯変, also called “fire change”) refers to the transformation of glaze colour caused by the way flame strikes the piece during firing. The same glaze under different flame conditions may emerge blue, red-purple, or brown — entirely unpredictable and unrepeatable.
Kan’nyū (Crazing) and Nyū (Body Crack)
Kan’nyū (貫入) is the network of fine cracks that forms in the glaze layer when the glaze and clay body contract at different rates during cooling. This is not breakage — the cracks remain within the glaze alone, and in good light they catch the light and add depth to the surface. Some potters deliberately emphasize kan’nyū by rubbing ink into the lines.
Nyū (入) is a crack that extends through the clay body itself. In the antique world, pieces where moisture seeps through a nyū to create surface staining are poetically called amamori (雨漏り, “rain leak”) and treasured for their wabi character. In everyday japanese ceramics, however, a nyū carries implications for hygiene and structural integrity that are worth considering.
Teppun — Iron Spots
Teppun (鉄粉) are black specks that appear when iron in the clay body oxidises during firing and rises to the surface. In white porcelain they are sometimes seen as imperfections, but in earthenware they read as warm, organic marks — small signs of the earth the clay came from.
Gohonte — Blush Marks
Gohonte (御本手) are soft pink or red-tinted flecks that appear on the surface of a fired piece. The effect has a gentle, almost blushing warmth to it — as though the piece has its own body temperature. Particularly loved on matcha bowls and tea cups (yunomi).
Meato — Stilt Marks
Meato (目跡) are the small marks left where pieces rested on or against each other during firing. They read as traces of the process — small evidence of how the piece was placed in the kiln.
Pinhole (Pinhōru)
Pinholes are tiny holes that resemble pinpricks, formed when air is trapped under the glaze during application or when bubbles escape during firing. They may appear as single points or scattered across the surface, adding texture and irregularity to the glaze.
Yū-damari — Glaze Pooling
Yū-damari (釉だまり) refers to areas where glaze has gathered thickly — typically at the rim, around the kōdai, or in the mikomi. The pooled glaze shows a deeper colour and a glass-like surface. It is named for the way glaze flows and collects, and it is one of the most visually striking effects in japanese ceramics.
The Joy of “Nurturing” Japanese Ceramics
Some of the keshiki described above are not fixed at the moment of firing — they continue to change with use. Kan’nyū in particular evolves over time, as do amamori stains. Japanese ceramic culture has a concept for this ongoing transformation: utsuwa wo sodateru (器を育てる, “nurturing a piece”) — the idea that a piece is not complete when it leaves the kiln, but continues to become itself in the hands of its owner.
The daily ritual of use, washing, and careful drying slowly changes the piece. Rather than “deterioration,” japanese ceramics culture sees this as a deepening — a piece acquiring character that only time and use can give.
Kan’nyū and Patina Over Time
The clearest expression of “nurturing” in japanese ceramics is the staining of kan’nyū. At first the crazing lines are nearly invisible — transparent and fine. Over months and years, the oils in food, the tannins in tea, and the natural residue of daily use slowly seep into these lines. On a white piece, a web of warm brown lines gradually emerges; eventually the whole piece takes on a rich, settled amber tone.
This is called kan’nyū ga somaru — the crazing absorbs colour. Like leather that develops a patina in the hand, the piece records the life of its owner in its surface.
There is far more to say about the pleasures of nurturing japanese ceramics than this article can hold:
The Poetic Amamori — Rain-Leak Staining
In pieces that have been used for a long time, a phenomenon called amamori (雨漏り, “rain leak”) sometimes appears: moisture that has entered through the clay body seeps outward and leaves faint, rain-like stains on the surface.
In practical terms this is close to a stain or leak, and in everyday use it is something to be aware of. But in the world of the tea ceremony and among those who love japanese ceramics deeply, these marks — reminiscent of rain seeping through an old earthen wall — are given a poetic name and appreciated for the quiet wabi they carry.
To find beauty even in an accidental stain by seeing it as rain falling from the sky: this is wabi-sabi at its most intimate.
Knowing the parts of a piece and understanding the traditional unit of sun makes choosing japanese ceramics far more enjoyable. A piece changes slowly with daily use, expressing itself in ways unique to how you live — becoming, over time, a piece that belongs entirely to you.
A piece with the “joy of nurturing” is one you keep indefinitely; eventually it becomes something you want to pass on.
Ceramics Rooted in Human Scale: Nurturing Keshiki Through the Daily Table
What once seemed like a puzzling “○-sun” notation begins to feel warm and familiar once you know it was born from the width of a thumb, the reach of an arm — the body’s own measure. The rightness of a 4-sun sharing plate in the hand, the way a 7-sun main dish plate sits comfortably between japanese and Western food: these are not accidents of tradition but the result of design calibrated to how humans actually live. Measuring out 12 cm and 21 cm on a ruler while comparing with what you already own, and then imagining your next piece from an online shop — that, too, is one of the pleasures particular to japanese ceramics.
Knowing the names of a piece’s parts and the vocabulary of keshiki is not merely accumulating knowledge. It is a passport to dialogue with the piece itself: a way of feeling the motion of a potter’s hand as they trimmed the kōdai, of witnessing the moment in the kiln when flame and clay did something unexpected.
The pristine condition of a newly bought piece is not its completion — it is its starting point. Serve food on it. Wash it with care. Let it breathe in a well-ventilated place. Through that quiet daily routine, a pattern of kan’nyū staining or the quiet shadow of amamori will gradually write itself into the surface: a story that belongs to no one else. We invite you to welcome japanese ceramics — rich with traditional wisdom and aesthetic depth — onto your table, and to begin the pleasure of watching them grow.
Related Articles & Guides
Learn More About Japanese Ceramic Culture & History
- The History of Japanese Ceramics
- The Aesthetic of Wabi-Sabi Hidden in Japanese Ceramics — Nurturing a Japanese ceramic
- What Wabi-Sabi Ceramics Bring Into our Life
- Japanese Ceramics That Grow: How Handmade Pottery Changes and Deepens with Every Use
- Japanese Pottery and Ichigo-Ichie: The Beauty of One-of-a-Kind Handmade Pieces
- Japanese Pottery Keshiki: How to Read Glaze Drips, Flame Marks, and Kiln Effects
Learn More About Japan’s Kiln Regions
How to Choose Japanese Ceramics
- Why Japanese Pottery Is Worth Owning
- Japanese Stoneware and Porcelain Explained
- Japanese Pottery: Earthenware, Stoneware and Porcelain Explained
- How to Choose Japanese Rice Bowl
- Japanese Sake Cups: Ochoko, Sakazuki, Guinomi and the Complete Guide to Sake Ware
How to Purchase Japanese Ceramics
Where to Buy Japanese Tableware Online
Looking for authentic japanese pottery for sale? Whether you are building your first collection of japanese tableware or searching for japanese gift ideas, Nokaze connects you directly with ceramic artists and kiln studios across Japan. Browse ochoko sake cups, rice bowls, serving platters, and one-of-a-kind pieces — each presented with the story of its maker and its kiln region.