What developers build with the Composite API
The Composite API endpoint (POST /v1/composite, Standard plan, 2.0 credits) analyzes relationship dynamics between two Human Design charts. You send two birth datetimes, and the API returns a complete composite analysis including shared Channels, electromagnetic pairs, compromise Channels, and Center dominance patterns.
This is the foundation for relationship apps, matchmaking features, and couple coaching platforms.
What the API returns
The composite response includes:
- Shared Channels — Channels that both people have defined independently. These represent consistent, reliable energies in the relationship.
- Electromagnetic Channels — When person A has one Gate of a Channel and person B has the other. These create magnetic attraction and are the strongest compatibility signal in Human Design.
- Compromise Channels — Channels where both people share the same Gate but neither completes the Channel. These can create tension or bonding around similar themes.
- Center Dominance — Which person’s definition dominates each Center, showing where each partner leads in the relationship.
Set verbose=true for gate-level detail including line, color, and tone data.
Example: Compatibility check
curl -X POST https://api.humandesignhub.app/v1/composite \
-H "X-API-KEY: YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"a": {"datetime": "1990-01-15T14:30:00+09:00"},
"b": {"datetime": "1992-06-22T08:15:00-05:00"}
}'Use case scenarios
Dating and matchmaking apps — Score compatibility based on electromagnetic channel count and shared definition patterns. Surface the most meaningful connections.
Couple coaching platforms — Generate relationship reports for Human Design practitioners to use with their clients. Highlight areas of natural flow and potential friction.
Team pairing tools — Use composite analysis alongside Group Penta to optimize team sub-pair assignments in work contexts.
Family dynamics apps — Analyze parent-child, sibling, or extended family dynamics to help families understand interaction patterns.
Why use the API
Computing a composite chart manually requires calculating two full bodygraphs and then performing overlay analysis across all 9 Centers, 64 Gates, and 36 Channels. The API does this in a single POST request.