Complements API

What goes with this? Answered instantly.

The Prodx Complements API returns products that genuinely complement a given item, organized into meaningful groups. Ask for complements to sliced bread and get food storage containers, nut butters (different types), fruit spreads, bananas, and avocados. Each group is named and scored, built from real purchase patterns and product attribute relationships.

See It In Action

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Why Grocery Cross-Sell Is Usually Guesswork

Most engines recommend more of the same item instead of what actually goes with it. That limits basket growth and creates noisy cross-sell modules.

Redundant Suggestions

Recommending peanut butter with more peanut butter misses the buying moment.

No Grouping Logic

Retailers need useful clusters such as spreads, storage, or meal pairings.

Low Basket Relevance

Generic cross-sell modules do not reflect how people actually plan meals or usage.

How Prodx Structures 'Goes With' Relationships

Prodx returns complements in named groups such as Nut Butters, Fruit Spreads, Fresh Bananas, or Food Storage Containers so cross-sell feels intuitive and immediately useful.

Pass a product ID to receive complement groups with ranked products.
Use real purchase patterns and attribute relationships to determine which products truly go together.
Return meaningful group names that improve merchandising and UI clarity.
Power 'Complete your meal' carousels, PDP cross-sells, and cart suggestions.
Differentiate complements from affinities or generic 'also bought' modules.

Measurable Impact

Grouped complements drive higher basket sizes than flat “also bought” lists. Retailers using Prodx Complements see measurable increases in items-per-order by surfacing genuinely useful product pairings instead of noise.

Higher

Items per order

Grouped complements drive stronger basket expansion than flat lists.

Better

Cross-sell relevance

The products shown reflect use-case context, not random adjacency.

Cleaner

Merchandising modules

Grouped outputs make placement and storytelling easier.

How a Top-10 Grocer Expanded Basket Size

See how a leading grocery retailer expanded basket size by surfacing relevant complementary products—turning single-item purchases into multi-item carts.

Read the Full Story

Technical Specifications

Every Prodx API is designed for real-world retail environments — high volume, low latency, and continuous data updates. From authentication to uptime guarantees, everything is engineered to integrate cleanly and scale with your business.

Response Format

JSON

Authentication

API key (provided at onboarding)

Rate Limits

Configured per retailer at contract level

Hosting

Prodx-managed cloud infrastructure

Latency

Sub-200ms typical response times

Availability

99.9% + uptime SLA

Data Refresh

Continuous. Product data updates propagate within minutes of catalog changes.

Integration

RESTful API. Standard HTTPS. No SDKs required.

Onboarding

Three weeks typical. Send us your product feed, we handle the rest.

Support

Dedicated account team. Direct engineering access for integration questions.

GET /v1/complements?catalogId=GEN_CATALOG &productId=960038380 &count=20
{
  "complementsGroups": [
    {
      "id": "NUT_BUTTERS",
      "name": "Nut Butters",
      "complementsProducts": [
        { "productId": "960039100", "score": 91 },
        { "productId": "960039112", "score": 85 }
      ]
    },
    {
      "id": "FRUIT_SPREADS",
      "name": "Fruit Spreads, Jams & Jellies",
      "complementsProducts": [
        { "productId": "960055200", "score": 94 }
      ]
    },
    {
      "id": "FOOD_STORAGE_CONTAINERS",
      "name": "Food Storage Containers",
      "complementsProducts": [
        { "productId": "960412033", "score": 88 },
        { "productId": "960412045", "score": 82 }
      ]
    },
    {
      "id": "FRESH_BANANAS",
      "name": "Fresh Bananas",
      "complementsProducts": [
        { "productId": "960001001", "score": 79 }
      ]
    }
  ],
  "complementsRequest": {
    "catalogId": "GEN_CATALOG",
    "productId": "960038380",
    "count": 20
  }
}