Polar API
Integration
The Polar API covers training sessions, heart rate, HRV, sleep, and nightly recharge from Polar Flow. Open Wearables handles OAuth, data sync, and normalization. One unified API for your app.
What you get from the Polar API.
Run, bike, swim, 100+ sport types
Resting, peak, average per session
Orthostatic test, nightly HRV4T
Stages, duration, sleep score
ANS charge, sleep charge
Cardio load, muscle load
Daily steps, active time
Running and cycling estimate
During sleep
Nightly deviation
How Polar API integration works.
User connects their Polar account
Open Wearables handles the Polar API OAuth flow. Your users authorize access through Polar Flow's standard consent screen. Token management is handled automatically.
Data is normalized to a unified schema
Training sessions, sleep, HRV, nightly recharge, and activity data from Polar are ingested and mapped to Open Wearables' unified health data schema. Consistent structure across all connected providers.
Your application calls one unified API
The same endpoints work for every provider. No Polar-specific parsing logic, no managing Polar Flow's webhook callbacks directly.
Polar is just the start.
One unified health data API, every provider. Plus health scores and AI reasoning.
All providers, one schema
Garmin, Whoop, Oura, Strava, Apple Health, Suunto, Samsung Health, Google Health Connect. Same endpoints, same data format.
See all providers →Open health scores
Sleep, recovery, strain, stress, HRV, VO2 max. Open algorithms you can audit and tune for your population.
Explore scores →AI reasoning engine
MCP server for any LLM. Detect trends, flag anomalies, build coaching profiles for wellness, performance, or clinical use cases.
Learn more →Open Wearables vs SaaS vs native Polar API.
| Aspect | Native Polar API | SaaS APIs | Open Wearables |
|---|---|---|---|
| OAuth implementation | You build and maintain it | Handled by provider | Handled by Open Wearables |
| Webhook callbacks | You build and host callback endpoints | Handled by provider | Handled by Open Wearables |
| Data normalization | Polar-specific data format | Unified schema, vendor-hosted | Unified schema, self-hosted |
| Multi-provider support | Separate integration per provider | One API, vendor infrastructure | One unified API, your infrastructure |
| Per-user pricing | No platform fee | Charged per connected user | $0 per user |
| Data ownership | You own all data | Vendor stores your users' data | You own all data |
| API version changes | Your team tracks and adapts | Vendor absorbs changes | Open Wearables absorbs upstream changes |
← scroll to see all →
Why Open Wearables for Polar.
Training-first data
Polar's strength is training analytics. HRV4Training integration, nightly recharge, and cardio load give you a picture of athlete readiness that complements passive recovery devices.
Nightly Recharge and HRV
Polar's nightly recharge score combines ANS charge and sleep charge. Open Wearables exposes both components alongside raw HRV data through the same API.
No Polar-specific logic in your backend
No need to learn Polar Flow's response format or webhook structure. Your application queries one schema regardless of the provider.
Combine with other providers
Pair Polar training data with Oura sleep or Whoop recovery in one query. One schema, every device.
Up and running in minutes.
GET /v1/events/workouts
{
"date": "2026-01-15",
"source": { "provider": "polar", "device": "Polar Vantage V3" },
"type": "run",
"distance_m": 10200,
"hrv_rmssd_ms": 52.1,
"nightly_recharge_score": 71,
"training_load": 142
}
Open Wearables is open-source and self-hosted. To use the Polar integration, register your application at the Polar Developer Portal and configure your credentials in your deployment.
Polar training data in your app,
without the integration overhead.
Open Wearables handles OAuth, webhook callbacks, and normalization. MIT licensed. $0 per user.
Common questions.
Do I need Polar API credentials?
Yes. You need to register your application at the Polar Developer Portal and obtain API credentials. Open Wearables handles the OAuth flow and data layer, but the credentials are yours to obtain directly from Polar.
What Polar metrics does Open Wearables expose?
Training sessions, heart rate, HRV, sleep, nightly recharge, training load, steps, VO2 max, breathing rate, and skin temperature. Full schema is in the docs.
Does Open Wearables support Polar webhook callbacks?
Yes. Open Wearables handles Polar's webhook callbacks and syncs new data automatically. Your application does not need to host or manage callback endpoints directly.
Which other providers can I connect alongside Polar?
Open Wearables currently integrates with Garmin, Whoop, Strava, Apple Health, Samsung Health, Google Health Connect, Suunto, and Oura. All providers share the same unified API schema.
Is Open Wearables production-ready?
Yes. Open Wearables is actively maintained and used in production. Check the GitHub releases for the current status of each provider integration.
Open Wearables is built and maintained by Momentum, a digital health agency reshaping healthcare through technology. Since 2016, they have been turning medical discoveries into compliant, scalable digital solutions. Momentum offers commercial services on top of Open Wearables for teams that need custom integrations, enterprise deployment, or SLA-backed support.
themomentum.ai →Other integrations
One API. Every provider. Zero per-user fees.
Deploy Open Wearables on your infrastructure. MIT licensed. Self-hosted.
