How to read Japanese product model numbers
A model number is not a name. It is a compressed spec sheet. Three systems — tools, model kits, barcodes — side by side.
Published · 日本語で読む →
Japanese products pack a lot of information into their codes. Using KTC tools, Gunpla grades and JAN barcodes as examples, this note shows the pattern they share, and why the code alone is never enough.
Key takeaways
- Most Japanese model numbers run in the same order: brand → type → size → spec → variant.
- The rules differ by maker, and official decoding guides are rare. Parts of what follows are our own reading.
- A single trailing letter (S, F, L…) can make it a different product, with a different length or head.
- The most reliable identifier is the JAN barcode. Codes issued to Japanese companies start with 45 or 49 — which says nothing about where the product was made.
- A model number is a clue, not proof. Confirm against the official spec sheet.
A model number is not a name. It is a spec sheet, compressed.
Three systems, side by side
Tools: KTC
N BR 2 90 S
- N … nepros line
- BR … ratchet handle
- 2 … 6.3 sq. drive (3 = 9.5 sq., 4 = 12.7 sq.)
- 90 … gear teeth
- S … short (F = flex, L = long)
Model kits: Gunpla
HGUC 191 1/144
- HG … grade (level of detail, usual scale)
- UC … Universal Century series
- 191 … running number within that series
- 1/144 … scale
Retail: JAN code
49 … … C
- 13 digits (standard type)
- start … GS1 company prefix (45 or 49 in Japan)
- middle … item reference set by the company
- last digit … check digit
The KTC breakdown is our reading from comparing catalog entries, not a decoding table published by KTC. Special editions and set-only items can break the pattern.
The shared pattern
Different systems, same order:
- Brand / series — whose, and which line (N, HG)
- Type — what kind of product (BR)
- Size / scale — drive size, scale, capacity
- Spec — tooth count, running number, generation
- Variant — the suffix: length, shape, limited or regional edition
Gunpla grades
For Gunpla (made by BANDAI SPIRITS), the grade tells you the usual scale and level of detail.
| Grade | Usual scale | Positioning (summarised from the maker) |
|---|---|---|
| EG | 1/144 | Entry level, few steps |
| HG | 1/144 | The broadest, core range |
| RG | 1/144 | High detail at small scale |
| MG | 1/100 | Larger; many have an inner frame |
| PG | 1/60 | Large and most detailed |
Our reading
Two listings for "the same Gundam" can be an HG and an MG — different size, part count and build time. Check the grade before the price.
Tamiya item numbers
Tamiya kits carry five-digit item numbers whose leading digits usually signal the series and scale.
| Starts with | Usual series |
|---|---|
| 35xxx | 1/35 Military Miniature |
| 24xxx | 1/24 Sports Car |
| 14xxx | 1/12 Motorcycle |
| 61xxx | 1/48 aircraft |
| 60xxx | 1/72 aircraft |
These are conventions with exceptions. A listing that says "1/35" but shows a 24xxx number is worth a second look.
"49" does not mean "made in Japan"
Fact
A standard 13-digit JAN code is a GS1 company prefix, an item reference and a single check digit. Company prefixes issued to Japanese businesses start with 45 or 49.
Our reading
The leading digits show which country's GS1 office issued the code, not where the product was made. "Starts with 49" does not prove Japanese manufacture, and a Japanese brand's product with another prefix is not automatically fake. Use a JAN code to pin down the exact item, not its origin: if a listing shows one, search it and see whether you land on the same product.
Listing words worth knowing
| Japanese | Reading | Meaning |
|---|---|---|
| 新品 | shinpin | New |
| 未開封 | mikaifū | Unopened, sealed |
| 未組立 | mikumitate | Unbuilt (box may be opened) |
| 中古 | chūko | Used |
| 再販 | saihan | Reissue, new production run |
| 限定 | gentei | Limited |
| 箱傷み | hako itami | Box damage |
| 説明書なし | setsumeisho nashi | No instructions |
Why the code alone is not enough
- Reissues and revisions. The same name can return with changed specs or contents.
- Regional versions. Domestic and export versions can differ in suffix, voltage or accessories.
- Exceptions. Limited, set-only and anniversary editions often get their own numbering.
Before you buy
- Match the model number down to the last letter
- If a JAN code is shown, search it and check you reach the same item
- Compare with the maker's product page or catalog spec table
- Check condition words: reissue, limited, used, unbuilt
Sources & references
- KTC catalog flyer: nepros 6.3 sq. ratchet handles and variants (Japanese) ktc.jp (PDF)
- GS1 Japan, "What are GS1 company prefixes and GTIN (JAN codes)?" (Japanese) gs1jp.org
- BANDAI SPIRITS hobby site bandai-hobby.net
- Tamiya official site tamiya.com
- Related note: Reading the KTC nepros NBR290 from its specs
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