# Xiaomi Mi Scale BLE Body Composition Scale # Copyright 2026 Pigs Can Fly Labs LLC # SPDX-License-Identifier: Apache-2.0 device: name: "Xiaomi Mi Scale Body Composition Scale" manufacturer: "Xiaomi / Huami" manufacturer_status: "unsupported" protocol: "ble" notes: > Xiaomi Mi Scale v1 and v2 body composition scales. v1 is weight-only; v2 adds impedance measurement for body composition (body fat, muscle, water, bone mass, visceral fat, BMR). Price $20-30. PROTOCOL: uses BLE standard Weight Scale service (0x181D) plus a custom Mi vendor service (0x1530) for v2 configuration. Weight readings arrive as live 13-byte (v2) or 10-byte (v1) notifications. History data is downloaded via a handshake protocol on characteristic 0x2A2F. WEIGHT FRAME (10-byte, both variants): [ctrl_byte] [weight_lo] [weight_hi] [year_lo] [year_hi] [month] [day] [hour] [min] [sec]. Control byte bits: Bit0=LBS, Bit4=Jin, Bit5=Stabilized, Bit7=WeightRemoved. Valid only when Bit5=1 AND Bit7=0. Weight division: /100 for lbs/jin, /200 for kg. v2 LIVE FRAME (13-byte): extends 10-byte format. Control byte 1 bits: Bit0=LBS, Bit1=hasImpedance. Control byte 2 bits: Bit5=Stabilized, Bit6=isCatty, Bit7=WeightRemoved. Impedance at bytes 9-10 (uint16 LE) when hasImpedance=1. HISTORY DOWNLOAD: enable notify on 0x2A2F, write magic `01 96 8A BD 62`, write "only last" marker `01 FF FF `, write trigger `02`. Data arrives as 10-byte records ending with `03` stop byte. Finish with `03` ack and `04 FF FF ` acknowledge. V2 ONLY: set scale unit via vendor characteristic 0x1542 under service 0x1530 with `06 04 00 ` (0=kg, 1=jin, 2=lbs). DISCOVERY: advertised names: "MIBCS", "MIBFS", "MI SCALE2", "MI_SCALE_*". Service UUID 0x181D is present on both v1 and v2. Service 0x1530 is v2-only. CONFIDENCE: HIGH for all UUIDs, weight frame format, control bits, history protocol, and v2 impedance frames — sourced from github.com/oliexdev/openScale, a production Android app with years of real-world use across hundreds of users. identification: service_uuids: - "0000181d-0000-1000-8000-00805f9b34fb" discovery: methods: - type: "ble_scan" ble: service_uuids: - "0000181d-0000-1000-8000-00805f9b34fb" identity: stable_keys: ["address"] display: "local_name" static_ip_required: false setup: required: false confidence: "high" notes: > No provisioning. Scale advertises when stepped on or powered. For history download, sync current time to 0x2A2B before requesting data. methods: - type: "ble_direct" verified: true description: > Scan for 0x181D service, connect, subscribe for weight notifications. No pairing required for basic reading. ble: pairing_required: false steps: - action: "Step on scale to wake it." actor: "user" request: protocol: "ble_gatt" - action: > Scan for 0x181D Weight Scale service or known name prefixes (MIBCS, MIBFS, MI_SCALE) and connect. actor: "client" - action: > Subscribe to notifications on 0x2A9D (weight measurement) and/or 0x2A2F (history). actor: "client" factory_reset: confidence: "low" effect: > Remove battery to clear internal state. No credential storage. procedures: - name: "Battery removal" steps: - action: "Remove batteries for 30 seconds and reinsert." actor: "user" expect: "Scale resets and advertises." rejoin: in_place_supported: true requires_factory_reset: false notes: "No bonding. Scale accepts connections from any central." credentials: wifi_passphrase_protection: "not_applicable" stored_on_device: [] issued_to_client: [] notes: "BLE-only. No auth. Health data — handle with privacy awareness." variants: - model: "Mi Scale v1" identification: local_name_prefix: "MI_SCALE" notes: > Weight only, no impedance. Service 0x181D. 10-byte frames. History on 0x2A2F under 0x181D. No vendor service. - model: "Mi Body Composition Scale v2" identification: local_name_prefix: "MIBCS" notes: > Body composition via impedance. Service 0x181B (primary) + 0x1530 vendor service. 13-byte live frames with impedance. Unit config via 0x1542. - model: "Mi Body Composition Scale (MIBFS)" identification: local_name_prefix: "MIBFS" notes: "Same as v2, different advertised name prefix." - model: "Mi Scale 2" identification: local_name: "MI SCALE2" notes: "v2 capabilities." services: - uuid: "0000181d-0000-1000-8000-00805f9b34fb" name: "Weight Scale Service" notes: > Standard BLE Weight Scale service. Primary for v1; alternate for v2. Carries weight measurement (0x2A9D), weight scale feature (0x2A9E), current time (0x2A2B), and Mi history (0x2A2F). characteristics: - uuid: "00002a9d-0000-1000-8000-00805f9b34fb" name: "Weight Measurement" properties: ["notify"] notes: > Standard BLE Weight Measurement characteristic. Often absent on Mi scales — weight arrives via 0x2A2F instead. When present, carries 10-byte weight frame. - uuid: "00002a2f-0000-3512-2118-0009af100700" name: "History" properties: ["write", "notify"] notes: > Custom history characteristic. Write magic bytes `01 96 8A BD 62` to enable, then `01 FF FF ` for "only last", then `02` to trigger transfer. Data arrives as 10-byte records. Stop marker is single byte `03`. Acknowledge with `03` then `04 FF FF `. - uuid: "00002a2b-0000-1000-8000-00805f9b34fb" name: "Current Time" properties: ["write"] notes: > Write current time before history download: `[year_lo, year_hi, month, day, hour, min, sec, 0x00, 0x00, 0x01]` - uuid: "00001530-0000-3512-2118-0009af100700" name: "Mi Vendor Service (v2 only)" notes: > v2-only. Provides unit configuration via 0x1542. characteristics: - uuid: "00001542-0000-3512-2118-0009af100700" name: "Mi Config" properties: ["write"] notes: > Set scale unit: `06 04 00 ` where 0=kg, 1=jin, 2=lbs. - uuid: "0000181b-0000-1000-8000-00805f9b34fb" name: "Body Composition Service (v2 only)" notes: > v2 primary service. Carries history, current time, and weight measurement for v2 scales. entities: - platform: "sensor" name: "Weight" state_characteristic: "00002a9d-0000-1000-8000-00805f9b34fb" - platform: "sensor" name: "Impedance" state_characteristic: "00002a2f-0000-3512-2118-0009af100700" - platform: "select" name: "Unit" state_characteristic: "00001542-0000-3512-2118-0009af100700" state_mapping: "0": "kg" "1": "jin" "2": "lbs"