Categories and attributes on OTTO: required fields, filters and visibility

Why the category decides so much

The OTTO Market API defines a category as a distinguishable part of the otto.de assortment identified by a name. Each category clusters the attributes that can describe its products – some obligatory, some optional. So the category determines which fields you can fill at all, where the product appears in the navigation and which filters shoppers can apply to it.

According to OTTO's FAQ, sellers can list in eight assortment areas: drugstore, furnishing & living, fashion & lifestyle, garden & DIY, health, non-perishable food, sports & leisure, and technology & media. Some product groups within them are, in the FAQ's words, "not yet sellable".

Retrieving the category list

The valid categories come from GET /v5/products/categories. The documentation is clear: the category name in your product data must match the name from this list exactly. Your own labels from the ERP ("Sofas & Couches" instead of OTTO's spelling) are rejected. Multichannel tools usually offer a mapping for this; check it after every change to the list.

Reading the attribute definitions

For each category, the API delivers the attribute definitions. The key fields according to the specification (as of October 2026):

• featureRelevance – where the attribute is used and where it appears in the shop, for example FILTER.
• type – the value format, such as string, integer or float.
• allowedValues – if set, only the listed values are permitted.
• unit – values must be transferred in the specified unit.
• multiValue – if true, several values can be sent (for example several materials).

LEGAL is mandatory, the rest makes you visible

Attributes with relevance LEGAL are mandatory – without them the variation doesn't go live. All other attributes are optional. The service provider Lengow puts it this way in its OTTO help: optional attributes should still be filled in because they increase visibility on otto.de; attributes are additionally classified by function, such as filter or navigation.

The reason is simple: if a shopper filters by "colour: grey" or "material: solid wood", otto.de only shows products where that attribute is set. A missing value is not a cosmetic flaw but a lost result.

Common category and attribute mistakes

1. Wrong category: the product appears in the wrong navigation and gets the wrong filters. Fix: check the category of a highly visible competing product and adopt it.
2. Free text instead of allowed values: "anthracite-grey" instead of the listed value from allowedValues is rejected or ignored.
3. Wrong unit: centimetres instead of millimetres gives dimensions off by a factor of ten – and wrong filter matches.
4. Only one value for multiValue: a product made of cotton and linen appears under only one material filter.
5. HTML in free-text fields: according to the documentation, description and bullet points accept only specific tags; other markup is removed.

Think attributes, title and search together

The product title gets the product into the result list, the attributes keep it there when shoppers filter, and the product description convinces on the detail page. If one of the three layers is missing, the product loses visibility that the title alone can't win back. So for every product with a weak ranking, first check which attributes of the category are empty.

Checklist and measuring the effect

• Category name exactly from GET /v5/products/categories.
• All LEGAL attributes filled in.
• All filter attributes (featureRelevance) with allowed values and the right unit.
• multiValue attributes with every applicable value.
• After upload: check the marketplace status for errors.

Whether added attributes work shows in the rankings of your search terms in the following weeks. MarktRank records the position daily, so you can see whether the product holds a better position after the change.

Frequently asked questions