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Health Connect reference

BodyWaterMassRecord: Health Connect body water mass data

Read from Google’s documentation on 2026-10-03 · Google’s reference page last updated 2026-06-24

BodyWaterMassRecord is Health Connect's body water mass record — an Instantaneous record in Google's Body Measurement category. Its read permission is android.permission.health.READ_BODY_WATER_MASS; its write permission is android.permission.health.WRITE_BODY_WATER_MASS. Google's reference defines no aggregate metrics on it, so it is read with readRecords rather than aggregate. Mandatory fields per Google's table: mass, metadata and time.

What Google says BodyWaterMassRecord is

Captures the user's body water mass. Each record represents a single instantaneous measurement.

Quoted from Google’s BodyWaterMassRecord Jetpack reference, last updated 2026-06-24, read 2026-10-03.

Class
androidx.health.connect.client.records.BodyWaterMassRecord
Google's category
Body Measurement
Record type
Instantaneous
Unit class
androidx.health.connect.client.units.Mass
Mandatory fields
massmetadatatime
Added in (Jetpack)
1.1.0

Permissions

The exact strings Google’s data-types table declares for BodyWaterMassRecord. Google’s page: “Before requesting any permissions, your app must declare them in the manifest.”

AccessPermission stringFramework reference
Readandroid.permission.health.READ_BODY_WATER_MASSAPI 34 · U Ext 7
Writeandroid.permission.health.WRITE_BODY_WATER_MASSAPI 34 · U Ext 7
AndroidManifest.xml
<uses-permission android:name="android.permission.health.READ_BODY_WATER_MASS" />
<uses-permission android:name="android.permission.health.WRITE_BODY_WATER_MASS" />
Kotlin — the same strings from the Jetpack helper
import androidx.health.connect.client.permission.HealthPermission
import androidx.health.connect.client.records.BodyWaterMassRecord

val permissions = setOf(
    HealthPermission.getReadPermission(BodyWaterMassRecord::class),
    HealthPermission.getWritePermission(BodyWaterMassRecord::class),
)

The 4 fields of BodyWaterMassRecord

Types and descriptions as Google’s reference prints them. The range column quotes Google’s own range annotation or sentence; a dash means Google states none, which is not the same as no validation.

FieldTypeAllowed rangeGoogle’s description
massmandatoryMassValid range: 0-1000 kilograms.Mass in Mass unit. Required field. Valid range: 0-1000 kilograms.
metadatamandatoryMetadata—Set of common metadata associated with the written record.
timemandatoryInstant—Time the record happened.
zoneOffsetZoneOffset?—User experienced zone offset at time, or null if unknown. Providing these will help history aggregations results stay consistent should user travel. Queries with user experienced time filters will assume system current zone offset if the information is absent.

Read BodyWaterMassRecord in Kotlin

The shape of Google’s own read example, with BodyWaterMassRecord and its names filled in. Get the client with HealthConnectClient.getOrCreate(context) after checking getSdkStatus.

readRecords
import androidx.health.connect.client.HealthConnectClient
import androidx.health.connect.client.records.BodyWaterMassRecord
import androidx.health.connect.client.request.ReadRecordsRequest
import androidx.health.connect.client.time.TimeRangeFilter
import java.time.Instant

suspend fun readBodyWaterMass(
    client: HealthConnectClient,
    startTime: Instant,
    endTime: Instant,
): List<BodyWaterMassRecord> {
    val response = client.readRecords(
        ReadRecordsRequest(
            BodyWaterMassRecord::class,
            timeRangeFilter = TimeRangeFilter.between(startTime, endTime),
        )
    )
    // One page of up to pageSize records (default 1000); follow
    // response.pageToken for the rest.
    return response.records
}

Setting up the client, the permission flow and Play Console declaration: integrating Health Connect step by step.

HealthKit counterpart

BodyWaterMassRecord sits in the verified cross-platform matrix’s Body composition row, which groups HKQuantityTypeIdentifier.bodyMass, .bodyFatPercentage, .leanBodyMass, .bodyMassIndex on Apple with WeightRecord, BodyFatRecord, LeanBodyMassRecord, BoneMassRecord, BodyWaterMassRecord, BasalMetabolicRateRecord on Android. The row groups the metric; it does not pair each Android record with one Apple type.

The Apple types in that row on the HealthKit reference: bodyMass, bodyFatPercentage, leanBodyMass, bodyMassIndex.

Watch out: The store holds it, but something has to write it — usually a smart scale or manual entry. Body fat is a bioimpedance estimate.

The metric on other platforms

This guide lists BodyWaterMassRecord beside the types on the other platforms this site covers whose own descriptions name the same metric, each quoted, with how each one is read.

Questions

What permission does BodyWaterMassRecord need?
Google's Health Connect data-types table (read 2026-10-03) declares android.permission.health.READ_BODY_WATER_MASS for reading BodyWaterMassRecord and android.permission.health.WRITE_BODY_WATER_MASS for writing it, and says apps must declare permissions in the manifest before requesting them.
Can you aggregate BodyWaterMassRecord with AggregateRequest?
Not directly. As read on 2026-10-03, Google's Jetpack reference defines no AggregateMetric constants on BodyWaterMassRecord, so there is no metric to put in an AggregateRequest. Read the records with readRecords and a ReadRecordsRequest, and compute any summary yourself.
What values does BodyWaterMassRecord.mass accept?
Google's reference types mass as Mass. Its description reads: "Mass in Mass unit. Required field. Valid range: 0-1000 kilograms."
Is BodyWaterMassRecord an interval, instantaneous or series record?
Google's data-types table lists BodyWaterMassRecord as Instantaneous, and defines that column as indicating "whether the data is recorded at an instant in time or over an interval". Its mandatory fields are mass, metadata and time.

Other Body Measurement records

All Body Measurement records →

Sources checked

Google’s descriptions are quoted for identification; the page layout, the capsule and the cross-platform pairing are AIFitnessAPI’s. Generated from Google’s pages by a script, not typed by hand — the same data is behind every page in the Health Connect reference.

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