Reference

Data formats

Tag grammar, CSV columns, metafield keys, year ranges.

Every grammar the app parses, in one place.

Product tags#

text

fits_<years>-<make>-<model>
fits_<years>-<make>-<model>-<submodel>

Part	Rules	Examples
Prefix	`fits_`, lowercase, required	`fits_`
Years	One year, or `from_to` inclusive	`2018`, `2010_2015`
Make	Lowercase, hyphens for spaces	`ford`, `land-rover`
Model	Lowercase, hyphens for spaces and slashes	`f-150`, `civic`
Submodel	Optional. Omit to match all submodels	`gt`, `trd-off-road`

text

fits_2018-ford-mustang-gt
fits_2010_2015-honda-civic
fits_2015_2026-ford-f-150

The grammar is the same whatever the product is. Shopify caps products at 250 tags, so use CSV for wide-fitment SKUs.

CSV and Google Sheets#

fitment.csv

SKU,Years,Make,Model,Submodel,Note
BP-CER-1142,2016-2021,Honda,Civic,,Front axle only
LK-6IN-F150,2015-2026,Ford,F-150,,Not with factory tow package
AF1-2090,2018-2024,Ford,F-150,Raptor,Requires hub ring
GHI789,2015|2017|2019,Toyota,Camry,,Track use only

Column	Required	Format
`SKU`	Yes	Matched to variant SKU, case-insensitive, trimmed
`Years`	Yes	`2019`, `2010-2023` (inclusive), or `2015	2017	2019`
`Make`	Yes	Free text, normalized before lookup
`Model`	Yes	Free text, normalized before lookup
`Submodel`	No	Blank means every submodel
`Note`	No	Shown to shoppers for that vehicle

Header matching is case-insensitive; extra columns are ignored.

Year ranges#

Input	Expands to
`2019`	2019
`2010-2023`	2010 … 2023 inclusive
`2010_2023`	Same (tag form)
`2015\|2017\|2019`	2015, 2017, 2019

Spec metafields#

Any metafield becomes a typed spec field once mapped — see the per-category examples. These wheel and tire keys are recognised without a mapping step, because the Fitment Data add-on needs to read them:

text

custom.wheel_diameter        decimal, inches
custom.wheel_width           decimal, inches
custom.wheel_offset          integer, millimetres, signed
custom.wheel_bolt_pattern    text, canonicalised
custom.wheel_hub_bore        decimal, millimetres
custom.tire_size             text, e.g. 275/55R20
custom.load_index            integer
custom.speed_rating          text

Any other metafield works after a mapping step. Index field prefixes by type:

Type	Prefix	Filter control
Decimal	`spec_num_`	Range
Integer	`spec_int_`	Range
Text, single	`spec_str_`	Dropdown / radio
Text, multi	`spec_strs_`	Checkboxes
Boolean	`spec_bool_`	Toggle

Canonical value formats#

Value	Canonical form	Accepted inputs
Make / model	`F-150`	`F150`, `f 150`, `F–150`
Bolt pattern (wheels)	`5x114.3`	`5×114.3mm`, `5-114.3`, `5x4.5"`, `5X114,3`
Any length	`20`, `9.5`, `6`	`20"`, `20.0`, `20 in`, `6 inch`
Offset	`35`, `-12`	`+35`, `35mm`, `ET35`
Hub bore	`87.1`	`87.1mm`, `87,1`
Tire size	`275/55R20`	`275/55/20`, `275-55-20`

Unit equivalences are physics and ship in code. Make, model and vocabulary spellings are per-shop synonyms.

Still stuck?

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