What are ACES and PIES, and do I need them?

ACES and PIES are the Auto Care Association's data standards for the automotive aftermarket. ACES describes fitment, meaning which vehicles a part fits; PIES describes the product itself. ACES refers to vehicles through the VCdb, a shared vehicle database. Most non-automotive categories have no equivalent standard.

Last updated October 25, 2026 · Nightshift Data

ACES: fitment

ACES (Aftermarket Catalog Exchange Standard) is the Auto Care Association's standard for managing and communicating product fitment data [1][2]. An ACES file says, for each part, which vehicle configurations it fits, with qualifiers such as position or engine. Because vehicles are referenced by database identifiers rather than free text, a retailer receiving the file can match it to their own vehicle lookup without guessing.

PIES: product information

PIES (Product Information Exchange Standard) is the companion standard for product information [3]: part numbers and identifiers, descriptions, dimensions and weights, packaging, prices and other attributes. Where ACES answers “what does it fit?”, PIES answers “what is it?”.

VCdb, PCdb and Qdb: the reference databases

Auto Care reference databases
Database	What it is	Used with
VCdb (Vehicle Configuration database)	The reference list of vehicles and their configurations	ACES [4]
PCdb (Product Classification database)	The reference list of part types and categories	ACES, PIES [5]
Qdb (Qualifier database)	Standard fitment qualifiers, such as conditions and notes on a fitment	ACES [6]

The databases are licensed by subscription through the Auto Care Association [1].

Why most other categories have no equivalent

ACES works because the automotive aftermarket agreed on one shared vehicle reference. Most other compatibility-critical categories never did. Marine engines, powersports machines, outdoor power equipment, appliances and bicycles each have their own model numbering, and fitment is kept in each manufacturer's or distributor's format: a spreadsheet, a PDF, or a sentence in a description.

For those categories, the fitment key has to be defined per category:

Fitment keys outside automotive
Category	Fitment is matched by
Powersports	Year · make · model · trim
Marine	Engine make · model · HP · serial range
RV & trailer	Model · chassis · size · weight rating
Outdoor power equipment	Equipment model · deck size · engine
Ag & heavy equipment	Model · serial range
Appliance parts	Appliance model number
Bicycle parts	Wheel size · axle · drivetrain · brake mount

ACES data and AI assistants

Having ACES data doesn't mean AI assistants can see it. ACES files move between suppliers, retailers and marketplaces; an assistant answering “will this fit my truck?” reads your product page. If the page shows only “fits 2015–2020 F-150”, the engine and submodel detail in the ACES file never reaches the shopper. See how to get auto and truck parts recommended by AI assistants and the complete guide to AI-ready parts listings.

Sources

Checked October 25, 2026. Platform rules and vendor offerings change; check the source for the current version.

Frequently asked questions

What is the difference between ACES and PIES?

ACES describes fitment: which vehicles a part fits. PIES describes the product itself: identifiers, descriptions, dimensions, packaging, prices and other attributes. Both are Auto Care Association standards, exchanged as XML.

What is the VCdb?

The Vehicle Configuration database: the Auto Care Association's reference list of vehicles and their configurations, such as engines and body types. ACES fitment refers to vehicles by their VCdb identifiers, so everyone describes the same vehicle the same way.

Do I need ACES and PIES to sell auto parts?

Not always. Many retailers, marketplaces and data pools in the automotive aftermarket work with ACES and PIES, so suppliers selling through them often need it. Smaller sellers on their own store may not, but they still need complete fitment on the product page.

Is there an ACES equivalent for marine, powersports or appliance parts?

Not one that's used across those industries the way ACES is in automotive. Fitment there is usually kept in each manufacturer's or distributor's own format, which is why it's so often incomplete or inconsistent.

Does having ACES data mean AI assistants can read my fitment?

No. ACES files are exchanged between businesses. An AI assistant answering a shopper reads your product page, so the fitment needs to be on the page as visible text and structured data.

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