Splits

Splits allow you to divide a line item's traffic into segments, each with its own targeting, CPM, and creatives. This is useful for A/B testing, geo-based pricing, or running different creatives for different audiences within the same campaign.

How splits work

When a line item has splits defined, the system evaluates each split independently:

1. Traffic allocation: Each split has a percentage (0 to 1). A random number is drawn and compared. If the random value is below the percentage, the split is considered for delivery.

2. Targeting: The split's targeting criteria are evaluated (AND logic). All criteria must pass.

3. Creative matching: The split's creatives are matched against the impression (dimension matching for banners).

4. Fallback: If no split is eligible, the line item's own creatives are used as a fallback (subject to dimension matching).

Split structure

Field	Type	Description
id	number	Unique split identifier
name	string	Split name
percentage	number	Traffic allocation ratio (0 to 1, where 0.5 = 50%)
cpm	number	CPM override for this split (0 = use line item rate)
targeting	object	Split-level targeting criteria
creatives	array	Creatives specific to this split
goal	number | null	Split-level delivery goal
goalType	string	impressions, clicks, or spend
pacingType	string	asap, even, or frontloaded
deliveryRatio	number	Dynamic delivery ratio (0 to 1), calculated by the pacing system

Split targeting

Line items and splits share the same Targeting shape. See the full attribute reference in Targeting. Each attribute uses { excluded: boolean, value: [...] } (or an array of { excluded, value: Record<string,string[]> } for the data-targeting variants).

Attribute	Description
geography	Country, region, or city (mixed levels supported)
domain	Publisher domain (wildcard support)
site	Nexx360 site ID
tagId	Nexx360 tag ID
page	Exact site.page URL
device	Device type
os	Operating system
browser	Browser (substring match on UA)
browserLanguage	Device language (prefix matching)
connection	Connection type
keyword	Page keywords
firstId	First-party ID from user.ext.eids (source first-id.fr)
dayandtime	Day of week + hour range (e.g. Monday 09:00–17:00)
viewabilityThreshold	Minimum viewability percentage
impData	Per-impression data (imp.ext.data)
siteAppData	Site or app data (site.ext.data, falls back to app.ext.data)
userData	User data (user.ext.data)

Day and time targeting example

Target weekdays during business hours:

{
  "dayandtime": {
    "excluded": false,
    "value": [
      { "day": ["Monday", "Tuesday", "Wednesday", "Thursday", "Friday"], "hours": { "start": "09:00", "end": "17:00" } }
    ]
  }
}

Data targeting example

{
  "userData": [
    { "excluded": false, "value": { "audience": ["premium"] } },
    { "excluded": true,  "value": { "category": ["adult"] } }
  ]
}

Split CPM

When a split has cpm > 0, that CPM overrides the line item's base rate for creatives delivered through that split. The split CPM is used in bid selection and appears in the bid response.

Delivery capping per split

Each split can be independently capped. See Pacing and Capping for details.