---
title: "Alertness period data (last 28 days)"
method: GET
path: "/v3/users/sleepwise/alertness"
tags: ["SleepWise™"]
---

# Alertness period data (last 28 days)

`GET /v3/users/sleepwise/alertness`

## Request

- Base URL: `https://www.polaraccesslink.com`
- URL: `https://www.polaraccesslink.com/v3/users/sleepwise/alertness`
- Auth: OAuth 2
  - Authorization code: `https://flow.polar.com/oauth2/authorization`
  - Token URL: `https://polarremote.com/v2/oauth2/token` scopes: `accesslink.read_all`
- TypeScript: <https://skmtc.dev/polar-com/apis/polar-accesslink-api/docs/v3/users/sleepwise/alertness/get.ts> (a function with typed inputs; its response is checked against the schema)

Get user's alertness period data for the last 28 days. <a href="https://support.polar.com/en/polar-sleepwise"> Supported devices </a>

## Response `200`

Request was successful.

- Alertness[]
  - `grade` number, double: Grade
  - `grade_validity_seconds` integer: Grade validity seconds
  - `grade_type` 'GRADE_TYPE_UNKNOWN' | 'GRADE_TYPE_PRIMARY' | 'GRADE_TYPE_ADDITIONAL': Grade type
  - `grade_classification` 'GRADE_CLASSIFICATION_UNKNOWN' | 'GRADE_CLASSIFICATION_WEAK' | 'GRADE_CLASSIFICATION_FAIR' | 'GRADE_CLASSIFICATION_STRONG' | 'GRADE_CLASSIFICATION_EXCELLENT': Grade classification
  - `validity` 'VALIDITY_UNKNOWN' | 'VALIDITY_RESET' | 'VALIDITY_NOT_VALID' | 'VALIDITY_ESTIMATE' | 'VALIDITY_VALID': Validity
  - `sleep_inertia` 'SLEEP_INERTIA_UNKNOWN' | 'SLEEP_INERTIA_NO_INERTIA' | 'SLEEP_INERTIA_MILD' | 'SLEEP_INERTIA_MODERATE' | 'SLEEP_INERTIA_HEAVY': Sleep inertia
  - `sleep_type` 'SLEEP_TYPE_UNKNOWN' | 'SLEEP_TYPE_PRIMARY' | 'SLEEP_TYPE_SECONDARY' | 'SLEEP_TYPE_ARTIFICIAL': Sleep type
  - `result_type` 'ALERTNESS_TYPE_UNKNOWN' | 'ALERTNESS_TYPE_PREDICTION' | 'ALERTNESS_TYPE_HISTORY': Result type
  - `period_start_time` string, date-time: Alertness period start time (UTC)
  - `period_end_time` string, date-time: Alertness period end time (UTC)
  - `sleep_period_start_time` string, date-time: Sleep period start time (UTC)
  - `sleep_period_end_time` string, date-time: Sleep period end time (UTC)
  - `sleep_timezone_offset_minutes` integer: Sleep timezone offset minutes
  - `hourly_data` AlertnessHourlyData[]: Alertness hourly data for the alertness period
    - `validity` 'VALIDITY_UNKNOWN' | 'VALIDITY_RESET' | 'VALIDITY_NOT_VALID' | 'VALIDITY_ESTIMATE' | 'VALIDITY_VALID': Validity
    - `alertness_level` 'ALERTNESS_LEVEL_UNKNOWN' | 'ALERTNESS_LEVEL_MINIMAL' | 'ALERTNESS_LEVEL_VERY_LOW' | 'ALERTNESS_LEVEL_LOW' | 'ALERTNESS_LEVEL_HIGH' | 'ALERTNESS_LEVEL_VERY_HIGH': Alertness level
    - `start_time` string, date-time: Alertness period start time (UTC)
    - `end_time` string, date-time: Alertness period end time (UTC)

## Other responses

- `204`: No data found for last 28 days.
- `400`: Invalid request.
- `401`: Unauthorized.
- `403`: User has not accepted all mandatory consents.

## Changes

- **2026-11-06** `18ce96365320`: 6 breaking
  - the `items/hourly_data/items/end_time` response's property format changed from `date` to `date-time` for status `200`
  - the `items/hourly_data/items/start_time` response's property format changed from `date` to `date-time` for status `200`
  - the `items/period_end_time` response's property format changed from `date` to `date-time` for status `200`
  - the `items/period_start_time` response's property format changed from `date` to `date-time` for status `200`
  - …2 more
- **2026-02-07** `f197848bba31`: 2 info
  - api tag `SleepWise&trade;` added
  - api tag `SleepWise&trade; (Beta)` removed
- **2025-06-04** `5ef2cea678a2`: 1 info
  - endpoint added

[Operation history](https://skmtc.dev/polar-com/apis/polar-accesslink-api/changes/v3/users/sleepwise/alertness/get.md)

---

[API](https://skmtc.dev/polar-com/apis/polar-accesslink-api.md) - [All operations](https://skmtc.dev/polar-com/apis/polar-accesslink-api/llms.txt) - [OpenAPI document](https://skmtc.dev/polar-com/apis/polar-accesslink-api/revisions/18ce96365320?raw)