How to Map CS2 Defindex and Paint Index to Market Hash Name

GET /v1/schema lets you narrow an item by def_index and paint_index, but that pair usually does not identify one tradable market row. You must still resolve exterior, StatTrak or Souvenir state, and any phase variant.

Use the full market_hash_name only after those attributes agree.

Understand what each index identifies#

def_index identifies the underlying weapon or item definition. paint_index identifies a paint kit. The same paint kit can appear on several weapons, and one weapon-paint combination can have several wear and edition rows.

Treat the pair as a candidate filter:

1. Match def_index.
2. Match paint_index where the row exposes it.
3. Select the exact exterior.
4. Select normal, StatTrak, or Souvenir state.
5. Resolve any nested phase or specialty variant.
6. Return the schema's exact market_hash_name.

If more than one candidate remains, the input is incomplete. Do not choose the first row.

Account for Doppler variants#

Base Doppler and Gamma Doppler rows can intentionally omit paint_index. Their nested phase records carry the phase-specific paint identity.

Search both top-level rows and documented variants. Keep the parent market name beside the phase label so a phase does not lose its weapon, exterior, or edition context.

This is especially important when the same phase paint index appears across multiple knife or glove families.

Preserve one-to-many results#

A paint index alone can map to many names. Even the def_index and paint_index pair can map to several wear states. Return a candidate set when exterior or edition is unknown.

A useful result includes:

• exact market_hash_name;
• def_index and paint_index;
• exterior;
• StatTrak and Souvenir state;
• parent and variant identity when applicable;
• schema generation_id.

Keep the resolver current#

The schema is available on all plans, supports ETag validation, and is cached for one hour. Store generation_id with derived mappings and rebuild them when that generation changes.

For the paint-only view, see map a CS2 paint index to skin names. To enumerate the wear candidates after resolving a finish, use every wear for a CS2 skin.