Every tile carton from a Chinese kiln carries a grade mark. Buyers see “AAA” in showrooms and “Grade A” on invoices and assume they mean the same thing. They usually do, but the terms are informal; the labels that matter are the Chinese ones on the box. This note explains what the grades mean, where they come from, what they do not tell you, and how much money is actually at stake when you choose between them.
The three grades
- First choice (youdengpin) – the top grade. Meets the national standard GB/T 4100 for dimensions, surface quality and physical properties with the tightest cosmetic tolerance. This is what is sold as “AAA”, “Grade A” or “premium” abroad.
- Second grade (yijipin) – the middle grade. Minor visible defects allowed under standard viewing conditions; dimensional tolerance slightly wider. Typically 15–25% cheaper.
- Third grade / qualified (hegepin) – the lowest saleable grade. Passes physical tests but with visible cosmetic defects. Fine for a garage; not for a living room.
Where the grade comes from
The grade is not a product line; it is a sorting result. Every tile that comes out of the kiln passes along a sorting line where cameras and inspectors classify it by surface defects and by how far it deviates from nominal size. The same firing run produces all three grades. On a well-run Foshan line, first choice is usually 85–95% of output, so second and third grade are by-products that the factory sells cheaply, mostly into the domestic budget market. The proportions vary with the design: heavily patterned or dark polished tiles show more defects and yield less first choice, which is one reason they cost more.
GB/T 4100 is aligned with the international standard ISO 13006, so the physical tests are the ones your engineer will recognise: water absorption (0.5% or less for porcelain), breaking strength and modulus of rupture, abrasion resistance, frost resistance, chemical and stain resistance, and crazing resistance for glazed tiles. All three grades have to pass those. What separates them is the cosmetic inspection: the standard sets a viewing distance and lighting level, closer for first choice and further for the lower grades, and requires at least 95% of tiles to show no visible defect at that distance. Dimensional tolerances tighten with grade in the same way.
What grading does not cover
Grade is about defects, not about design consistency between batches. Two other codes on the carton decide whether your floor looks uniform:
- Shade / colour number (sehao) – a letter or number indicating the firing batch’s colour. Mixing shades on one floor is the most common complaint we see.
- Calibre / size code (chima) – the actual fired size within tolerance (e.g. 798, 800, 802 mm). Mixing calibres produces uneven joints.
Neither is a fault. A kiln cannot hold colour and size perfectly constant from one week to the next, so it measures each batch and labels it. The failure is in the handling: a warehouse that picks from two batches, or a buyer who tops up six months later. A first-choice floor laid from two shades looks worse than a second-grade floor laid from one.
Reading the carton
| On the box | Meaning | What to check |
|---|---|---|
| Grade line (dengji) | First choice, second grade or qualified | Matches the pro-forma: first choice, not second or third grade |
| Shade code (sehao), e.g. A3 or 12 | Shade / colour batch | One code across every carton of that design |
| Calibre code (chima), e.g. 800 or 2 | Calibre / fired size | One code across every carton of that design |
| Production date | Production date | Close dates suggest one firing run |
| Model number | Model number | Matches the reference tile and the back-stamp |
Some kilns print the grade word on its own, some use a stamp, and some export cartons carry only English text with no Chinese grade at all. When the grade is missing from the carton it has to be on the pro-forma and the invoice instead, in Chinese, or you have no claim.
Grade and price: a worked example
Take a stock 800×800 polished glazed porcelain from a mid-sized Foshan kiln. Typical ex-works prices, which vary by design and season, might be RMB 45 per m² for first choice, RMB 36 for second grade and RMB 28 for third grade. On a 1,000 m² villa order the second grade saves about RMB 9,000, roughly USD 1,250, against a landed cost that is probably RMB 80,000–100,000 once freight, duty and delivery are added. In exchange, your installer has to sort out the tiles with visible marks, so the 5% extra you ordered becomes 10% or more, and the saving shrinks further. For living areas we do not recommend it. For a plant room, a store, a staff bathroom or a rental garage, second grade at RMB 36 is sensible money.
Export “grades” and what they mean
“AAA”, “AA”, “A”, “B”, “premium” and “standard” are trading terms with no defined meaning. In most cases a trader’s AAA is first choice, but we have seen second grade shipped under that label to markets where nobody reads Chinese. “B grade” or “second choice” at a discount is usually second grade, occasionally third grade. The cheapest offers of all are mixed or unsorted stock (hundeng), where the cartons have not been graded consistently and you get whatever comes off the pallet; some of it will be first choice and some of it will be unusable. Ask for the Chinese grade and the kiln’s model number every time, and check the back-stamp against the sample, which is how we trace which factory made a tile whatever name is on the carton. Our step-by-step tile buying guide goes through the ordering process in full.
Does the region matter?
The standard is national, but the sorting discipline is not. The large Foshan kilns run automated sorting with cameras and grade tightly, partly because their domestic brand customers will reject anything else. Smaller kilns in Foshan and in the clusters around Zibo and Jinjiang sort by eye and tend to be more generous with the first-choice stamp. The product can still be good, but the inspection before you pay the balance matters more, and we open more cartons. Tiles sold through export-only trading companies are the ones to watch most closely, because the carton is often reprinted in English and the original grade is gone.
Common mistakes
- Taking the showroom grade as read. The showroom tile is first choice by definition. The question is what leaves the warehouse.
- Buying second grade for a living room to save 20%. The saving is a few thousand RMB on an order that costs tens of thousands landed, and the marks are permanent.
- Accepting two shade codes because the factory says they are “very close”. They may be. Lay them side by side in daylight before you agree.
- Not writing the grade on the pro-forma. If the document says only “800×800 polished”, the factory has met the contract with third grade.
How to buy safely
- Write the grade on the pro-forma in both English and the factory’s own wording, so there is no ambiguity.
- Require one shade and one calibre for the whole quantity of each design, and have the batch numbers written on the invoice.
- Keep a sealed reference tile.
- At inspection, open cartons from several pallets and compare against the reference in daylight.
- Order 5–8% extra so you never have to top up from a different batch later.
At the factory we also measure a handful of tiles from different pallets with a steel rule and a straight-edge, check the back-stamp, and photograph the carton labels next to the pro-forma so there is a record of what was agreed and what was loaded. Clients who come on a buying trip see this done on their own order; for remote orders we send the photographs the same day. More in the tile buying guide.
A note on prices: every figure in this guide is an indicative estimate from recent orders. Factory prices, freight rates and exchange rates move, so treat them as a planning guide and ask us for a current quote before you budget.
Frequently asked questions
If I ask for first choice, will I always get it?
If it is written on the pro-forma in Chinese and you inspect before paying the balance, yes. Factories rarely substitute deliberately; the usual problem is a warehouse picking from the wrong pallet, or a trader relabelling. Both are caught by opening cartons and reading the labels, which takes an hour.
Is second grade ever worth buying?
Yes, for areas nobody looks at closely: garages, plant rooms, stores, staff facilities, some commercial back-of-house. Expect to sort out 5–10% of the tiles, order accordingly, and make sure the second grade is genuinely second grade rather than unsorted stock. For anything a client or tenant will see, buy first choice.
Can I get a test certificate for the tile?
Larger kilns hold recent third-party test reports to GB/T 4100 or ISO 13006 covering water absorption, breaking strength and slip resistance, and will provide them on request. Smaller kilns often do not. If your project needs certified figures, say so before choosing the factory rather than after, and we will steer you to one that can supply them.
What if the shade is slightly off when the tiles arrive?
If the inspection was done and the sealed reference tile matches what was loaded, the shade will not be off; that is the point of the procedure. If you skipped inspection, your recourse is limited to the factory’s goodwill, which for a small foreign buyer is not much. Prevention is cheap; a claim after shipping is not.
Do the grades apply to slabs and wall tiles as well?
Yes. GB/T 4100 covers all ceramic tiles, and the three-grade sorting is used for 1200×2400 slabs, glazed ceramic wall tiles and mosaics alike. Slabs are the one format where we suggest asking about the reject rate at sorting, because a visible pinhole on a 3 m² piece is expensive.
Planning to buy building materials in Foshan?
Tell us what you need and when you plan to come. We aim to reply the same business day with a realistic plan, price ranges and which markets to visit.