When you bring a new mug, plate, bowl, or handmade pottery piece into your home, one of the first questions you may ask is: “Are ceramics dishwasher safe?” It sounds simple, but the real answer depends on the type of ceramic, the glaze, the temperature it was fired at, and even how you load your dishwasher. If you want the safest, longest-lasting results for your ceramic dinnerware, cookware, and décor pieces, you need a deeper understanding than just “yes” or “no.”

In this expert-level guide, we’re going far beyond the basics. We’ll break down every type of ceramic, how they behave in dishwashers, what makes some dishwasher-friendly while others are not, the science behind glazes, and what manufacturers don’t always tell you. By the end, you’ll be more informed than 95% of consumers—and likely most bloggers, too.

Let’s dive in.

What Exactly Is Ceramic, and Why Does It Matter for Dishwasher Safety?

Before deciding whether ceramics are dishwasher safe, it’s important to understand the material itself. “Ceramic” is a broad term and includes multiple categories:

• Earthenware
• Stoneware
• Porcelain
• Bone china
• Ceramic-coated cookware
• Handmade pottery
• Decorative ceramics

Each of these types has different firing temperatures, porosity levels, and glaze technologies. Those factors determine whether a ceramic piece can handle intense water pressure, high temperatures, caustic detergents, and thermal shock inside a dishwasher.

Dishwashers are harsh environments. The combination of blasting water, alkaline detergents, and rapid heating/cooling creates stress on materials. Some ceramics are built to handle this; others aren’t.

How Firing Temperature Influences Dishwasher Safety

Ceramics go through a firing process where clay is transformed from a soft, moldable material into a hard, durable structure. The firing temperature directly affects durability and how ceramics behave in a dishwasher.

Earthenware (Low Fire: ~1,000°C / 1,830°F)

• More porous
• Softer and more fragile
• Often requires a thick glaze to create a sealed surface
• Can absorb moisture if the glaze isn’t perfect

Earthenware is usually not ideal for dishwashers unless specifically labeled dishwasher safe.

Stoneware (Mid to High Fire: ~1,200°C / 2,192°F)

• Denser and less porous
• Naturally stronger
• Better thermal shock resistance

High-quality stoneware is typically dishwasher safe.

Porcelain (High Fire: ~1,300°C / 2,372°F)

• Extremely dense
• Hard, glassy structure
• Virtually non-porous
• Withstands temperature fluctuations well

Porcelain is almost always dishwasher safe, unless it has metallic detailing (more on that later).

Bone China (High Fire + Bone Ash)

• Lightweight but durable
• Excellent thermal shock resistance
• Dense, vitrified surface

Also generally dishwasher safe, though extra care is needed for gold or platinum borders.

The Role of Glaze: The #1 Factor in Dishwasher Safety

Even if the clay body is strong, the glaze determines whether the ceramic can truly survive machine washing. The glaze is a glass-like coating fused to the ceramic surface during firing.

A dishwasher-safe glaze must be:

• Non-porous
• Lead-free or extremely low-lead
• Smooth without crazing or crackle effects
• Hard enough to resist scratching
• Stable under high heat and alkaline detergent

Crazing: The Hidden Threat

Crazing occurs when tiny spiderweb-like cracks develop in the glaze. It may look artistic, but it’s a structural weakness.

Problems caused by crazing in a dishwasher:

• Water and detergent can seep into the cracks
• Moisture gets trapped, causing mold or odor
• Thermal stress worsens the cracking
• Over time, the ceramic can weaken and break

Dishwashers greatly accelerate the crazing process.

Metallic Glazes and Gold Trim

Any ceramic with metallic elements—gold rims, silver accents, luster glazes—is at high risk in a dishwasher.

Machine washing can cause:

• Tarnishing
• Fading
• Peeling or flaking
• Color loss
• Dullness on glossy surfaces

For these types of ceramics, handwashing is essential.

Mass-Produced vs. Handmade Ceramics: A Big Difference

When asking “Are ceramics dishwasher safe?”, mass-produced ceramics and handmade pottery behave very differently.

Mass-Produced Ceramics

These usually come from factories with controlled conditions.

Advantages:

• Precise glaze application
• Consistent firing temperatures
• Certified dishwasher-safe labeling
• More resistant to chipping
• Minimal crazing

You can typically trust the dishwasher-safe label on reputable brands.

Handmade Ceramics

Each piece is unique—and so is its safety profile.

Risks include:

• uneven glaze thickness
• micro-cracking
• low firing temperatures
• softer clay bodies
• decorative finishes not meant for water pressure
• unknown glaze ingredients

Many potters recommend washing handmade ceramics by hand even if they seem sturdy.

Why Some Ceramics Break in the Dishwasher

If you’ve ever found a cracked mug or chipped plate after a wash cycle, here’s why it happens:

1. Thermal Shock

Dishwashers change temperature rapidly:

• Pre-rinse: cool
• Wash: hot
• Rinse: hotter
• Dry: extreme heat

Porous ceramics can’t handle this stress.

2. Water Absorption

Low-fired ceramics absorb water through microscopic pores. Inside the dishwasher, the water pressure forces even more moisture in.

As the piece dries:

• trapped water expands
• the ceramic weakens
• cracks form over time

3. Detergent Abrasion

Dishwasher detergent is alkaline and abrasive. It can:

• dull the glaze
• strip surface shine
• degrade artistic finishes
• encourage crazing
• expose clay underneath

4. Impact From Other Items

Ceramics knocking into metal utensils, heavy pans, or each other often leads to chips and cracks.

5. Poor Quality Control

Cheap ceramics (often imported with no safety certifications) may:

• contain unstable glaze
• have uneven thickness
• be under-fired
• contain harmful metals
• crack even after a few washes

These pieces are never dishwasher safe.

Which Types of Ceramics Are Safest for the Dishwasher?

Let’s break them down one by one.

✔ Dishwasher-Safe Ceramics

• Porcelain
• Bone china
• High-fired stoneware
• Vitrified commercial restaurant ceramics
• Most modern mass-produced ceramic mugs and plates
• Ceramic-coated stainless steel pans (check brand guidelines)

✘ Not Dishwasher Safe

• Earthenware
• Terracotta
• Raku pottery
• Low-fired decorative pieces
• Handmade pottery unless labeled safe
• Crackle-glazed ceramics
• Ceramics with metallic detailing
• Antique or vintage ceramics
• Low-cost ceramics without proper glazing certifications

Knowing these differences helps you protect your ceramics from damage.

The Dishwasher Test: How to Tell if Your Ceramic Item Is Safe

If your item isn’t labeled, here are ways to determine dishwasher safety.

1. The Fingernail Test

Run your nail lightly over the glaze:

• If it feels smooth → likely safe
• If you feel texture, ridges, or rough spots → avoid machine washing

2. The Absorption Test

Place a drop of water on the unglazed bottom:

• If it absorbs quickly → porous → not safe
• If it beads → dense → likely safe

3. The Ping Test

Tap the ceramic lightly:

• A clear ring = high-fired, strong
• A dull thud = low-fired, softer

4. Visual Glaze Check

Look for:

• crazing
• cracks
• matte patches
• shimmer or metallic flecks
• thick decorative paint

These signs indicate risk in the dishwasher.

5. Weight and Thickness

Denser, thinner ceramics (porcelain, bone china) survive better. Thick, heavy ceramics (low-fired pottery) absorb more heat and stress.

How Dishwashers Affect Ceramic Longevity

Even if your ceramic piece survives the dishwasher, long-term use still causes wear.

After 10+ Washes:

• slight dulling
• microscratches
• fading of decals

After 50+ Washes:

• noticeable loss of shine
• crazing may start to form on cheap ceramics
• tiny chips around rims

After 100+ Washes:

• glaze dramatically thins
• color fades (especially on cheaper pieces)
• edges wear down
• cracks become more visible

High-quality porcelain and stoneware show much less degradation.

Restaurant Ceramics: Why They Survive Better Than Home Ceramics

Commercial dinnerware used in restaurants goes through industrial dishwashers multiple times a day.

Why doesn’t it break?

• fired at extremely high temperatures
• fully vitrified (non-porous)
• thick glaze engineered for durability
• impact-resistant clay bodies
• no decorative paint or metallic trim
• uniform thickness prevents uneven stress

This is why restaurant-grade ceramic plates often last many years.

If you want maximum dishwasher safety, commercial-grade ceramics are one of the best options.

Ceramic Cookware: A Special Case

Ceramic-coated cookware (like nonstick ceramic pans) is not the same as traditional ceramics.

Even though they’re marketed as tough, many ceramic-coated pans should NOT go in the dishwasher because:

• detergent breaks down the nonstick coating
• dishwasher heat weakens bonding layers
• interior can discolor
• water exposure can cause thermal shock

Some brands allow dishwasher use, but handwashing is strongly preferred to extend lifespan.

When in Doubt, What Do Manufacturers Use to Decide Dishwasher Safety?

A ceramic product is labeled dishwasher-safe only if it passes industry tests:

ASTM Standards

Ensures:

• glaze stability
• chemical resistance
• impact resistance
• compatibility with alkaline detergents

Thermal Shock Tests

Ceramic pieces are rapidly heated and cooled to determine whether they can survive dishwasher cycles.

Abrasion and Detergent Testing

Simulated washing cycles evaluate glaze durability.

If a ceramic item doesn’t meet these tests, it cannot legally be advertised as dishwasher safe.

Signs Your Ceramic Item Should Stop Going in the Dishwasher

If you see any of the following, retire it from machine washing:

• new cracks or crazing
• color fading
• the bottom feels rougher than before
• water stains appear
• glaze looks matte instead of glossy
• chips around the rim
• strange smells from absorbed water

The dishwasher will only accelerate damage from here.