A specification sheet is the single document a Japanese factory, a testing laboratory and your own importer will all refer back to for the life of a product. Ask for a quotation before it exists and you will get a rough estimate at best; ask a factory to defend a batch without one and there is nothing to measure the batch against.
This guide sets out what a specification typically contains for a Japan-made supplement, why each item is there, and why a quotation only becomes accurate once the specification is fixed.
💬 Working from a sample rather than a written specification? That is the normal order of things. See Japan-made supplement OEM for how a specification gets built from an approved sample.
What goes into a specification
A specification names every ingredient and its amount, the dosage form and physical description, the safety limits the batch must meet, and how the finished product is stored and packaged.
| Section | What it fixes |
|---|---|
| Ingredients and amounts per serving | Every active and inactive ingredient (excipients, capsule shell material, coating, flavour, colour), with the exact amount in each serving |
| Dosage form and unit weight | Tablet, capsule, softgel, powder, jelly, drink or gummy, and the target weight or volume per unit, with an acceptable tolerance |
| Appearance | Colour, shape, size, surface texture — what a passing unit should look like, and what a defect looks like |
| Microbiological limits | Which organisms are tested for (commonly total viable count, coliforms, and for some products E. coli, Salmonella, yeasts and moulds) and the pass/fail limit for each |
| Heavy-metal and contaminant limits | Which metals are tested (commonly lead, arsenic, cadmium, mercury) and the limit for each, plus residual pesticide limits where the ingredient is plant-derived |
| Shelf life | The period the product is guaranteed to meet the specification from the manufacturing date, under stated storage conditions |
| Storage conditions | Temperature, humidity and light conditions the product must be kept under to reach that shelf life |
| Packaging | Primary packaging (bottle, blister, sachet, pouch) and any secondary packaging, with material and closure detail |
Japan does not set one universal numeric heavy-metal or microbiological limit that applies to every kind of health food; food-category standards under the Food Sanitation Act are set per food category, administered by the Consumer Affairs Agency since food-safety standard administration moved there from the Ministry of Health, Labour and Welfare on 1 April 2024, and some categories carry no category-specific numeric limit at all. This is exactly why the specification has to state its own numeric limits explicitly — a factory works to the numbers written in the document in front of it, whether those come from your target market’s own rules, a voluntary industry standard, or an agreement reached with the factory.
Why every quotation depends on it
Cost drivers — fill weight, coating, testing scope, packaging material, shelf-life target — are all specification decisions, so a quotation given before the specification exists is necessarily a rough estimate.
| Specification item | What it changes in the quotation |
|---|---|
| Ingredient amount and source | Raw material cost is the largest line item for most formulas |
| Dosage form and unit weight | Tooling, fill speed and shell or coating cost |
| Microbiological and heavy-metal testing scope | Which tests are run, and how often, on incoming material and finished batches |
| Shelf-life target | May require different packaging (barrier film, desiccant, oxygen absorber) to reach a longer target |
| Packaging material and format | Bottle, blister and sachet lines cost differently and run at different speeds |
A factory asked “what would this cost” before any of these are fixed can only answer in ranges wide enough to be close to meaningless. A factory asked against a finished specification can quote a specific number, because every input to that number is already decided.
💬 Have an approved sample but no written specification yet? We can turn it into one before you ask other factories to quote against it. Start the conversation.
Who writes the specification, and when
The specification is normally drafted by the factory after a sample is approved, then reviewed and signed off by the brand before production begins.
The sequence that avoids rework is: agree the formula, produce and approve a sample, write the specification against that approved sample, then quote and produce against the specification. A specification written before a sample exists is a target, not a confirmed fact, because some combinations of ingredients, dosage form and packaging behave differently in practice than on paper — taste, colour stability and disintegration time are the most common surprises. Building the specification from an approved sample, rather than the other way round, is what keeps the document accurate.
Gaps that commonly delay a first specification
The items most often missing from a brand’s first draft are testing frequency, tolerance ranges, and what counts as a defect — not the ingredient list.
Brands usually arrive with the ingredient list well defined, since that is the part they designed the product around. What is more often missing is how the specification is enforced in practice: how often each test runs (every batch, or a sampling schedule), what tolerance is acceptable around the target weight or fill volume, and what a factory should do with a batch that is close to a limit but not clearly over it. Settling these questions in the specification itself, rather than leaving them to be worked out when a borderline batch actually occurs, is what keeps a supplier relationship predictable.
Before you ask for a quotation
Have these ready, or be ready to work through them with the factory, before asking for a firm price.
- Every ingredient and its amount per serving
- Your preferred dosage form and target unit weight
- Whether you have an approved sample, or need one made first
- Your target shelf life and the storage conditions the product will actually see
- Your target markets, since some limits and label rules follow from them
- Your preferred packaging format
💬 Ready to turn a formula or a sample into a specification? Send us what you have and we will tell you what is still missing.
Frequently asked questions
1. Can I get a quotation without a full specification?
You can get a rough range, but not a firm quotation. Too many cost drivers — fill weight, testing scope, packaging — are specification decisions, so a number given before they are fixed is only an estimate.
2. Who sets the microbiological and heavy-metal limits in the specification?
They are usually set to meet the strictest of: your target market’s own legal limits, any voluntary industry standard the factory follows, and what is realistically achievable for the ingredients involved. They should be agreed and written down, not assumed.
3. Does the specification change if I add a new market later?
It can. A market with stricter limits than your original specification may require retesting or a formula adjustment, so it is worth naming every market you are likely to sell in before the specification is finalised, even if you plan to launch in one market first.
4. What happens if a production batch does not meet the specification?
That is what the certificate of analysis is for — it records the actual test results for the batch against the specification’s limits, so both sides can see clearly whether a batch passed. See our certificate of analysis guide.
5. Is the specification the same document as the label?
No. The specification is an internal manufacturing and testing document; the label is a separate, market-specific document built from some of the same information (ingredients, amounts, storage instructions) but formatted to your target market’s labelling rules.
Sources: Consumer Affairs Agency (food-safety standard administration transferred from the Ministry of Health, Labour and Welfare on 1 April 2024) and Ministry of Health, Labour and Welfare, “食品別の規格基準について” (mhlw.go.jp/stf/seisakunitsuite/bunya/kenkou_iryou/shokuhin/jigyousya/shokuhin_kikaku/), describing general component standards for all foods, manufacturing/processing/preparation standards, storage standards and individual food-category standards administered under the Food Sanitation Act; Japan Health and Nutrition Food Association (JHNFA/JHFA), description of its certification assessing appearance, labelled component content, and safety/hygiene indicators including residual pesticides, heavy metals and general bacterial/coliform counts (jhnfa.org/health7.html, jhnfa.org/health-02.html). Checked on 25 September 2026.