Blood Pressure Record (0x2B36): byte layout
GATT characteristic · org.bluetooth.characteristic.blood_pressure_record · read from the Bluetooth SIG’s repository on 2026-10-17 · commit 408f4a0 (2026-10-14)
Blood Pressure Record is Bluetooth GATT characteristic 0x2B36, org.bluetooth.characteristic.blood_pressure_record in the Bluetooth SIG's assigned numbers. The SIG's GATT Specification Supplement file lays its value out as 5 fields: Segmentation Header, Sequence Number, UUID, Recorded Characteristic and E2E-CRC.
- UUID
- 0x2B36
- Identifier
org.bluetooth.characteristic.blood_pressure_record- The SIG’s description
- The Blood Pressure Record characteristic is a container that represents a stored value of a blood pressure measurement or of any other characteristic as specified by the service using the characteristic.The structure of this characteristic is defined below.
- Service the SIG’s files tie it to
- None: no file in the repository lists this characteristic under a service.
- Source file
- gss/org.bluetooth.characteristic.blood_pressure_record.yaml
Byte layout: 5 fields
In the order the SIG’s structure lists them. Type and size are as published; sizes count octets except where a struct is marked as sized in bits. The offset is printed only where every earlier field has a fixed size; where an earlier field can be absent or vary, the cell names what it depends on. “Present when” is read from the field’s own “Present if” line, shown in full in the field notes below.
| Offset | Field | Type | Size | Present when | Unit |
|---|---|---|---|---|---|
| 0 | Segmentation Header | boolean[8] | 1 | Always (fixed size) | — |
| 1 | Sequence Number | uint16 | 2 | Always (fixed size) | — |
| 3 | UUID | uint16 | 2 | Always (fixed size) | — |
| 5 | Recorded Characteristic | Determined by UUID | Variable | Not stated in the field's text | — |
| Depends on the size of Recorded Characteristic | E2E-CRC | uint16 | 0 or 2 | Not stated in the field's text | — |
Field notes
Each field’s text in the SIG’s file, line by line.
- Segmentation Header boolean[8] · 1
- See Segmentation Header.
- Sequence Number uint16 · 2
- Contains a sequence number of the record. The sequence number starts at 0 and loops back to 0 after 65536 records (per user).See Sequence Number.
- UUID uint16 · 2
- Contains the UUID of the contained characteristic value.See UUID.
- Recorded Characteristic Determined by UUID · Variable
- Contains a part of or a complete characteristic value.See Recorded Characteristic.
- E2E-CRC uint16 · 0 or 2
- Contains the CRC over all the data of a complete single or multi-message record.See E2E-CRC.The presence of this field is defined by the service using this characteristic.
Flags and value tables
The definitions the SIG’s file gives for its fields, every row as published. On a flags table the last column lists the fields whose “Present if” line names that bit.
Segmentation Header
The Segmentation Header field provides information about which segments to concatenate to get a complete Blood Pressure Record value.The bits of this field are defined below.
| Bit | Description | Fields its condition names |
|---|---|---|
| 0 | First Segment: the characteristic contains the first segment of a record0 = False1 = True | — |
| 1 | Last Segment: The characteristic contains the last segment of a record0 = False1 = True | — |
| 2–7 | Rolling Segment Counter: 0 to 63If the Rolling Segment Counter is equal to 63, it rolls over to 0 when it is next incremented. | — |
Sequence Number
The sequence number field contains the sequence number of a record. The sequence number starts at 0 and loops back to 0 after 65536 records and is used to number a sequence of records as defined by the service.
UUID
The UUID field contains the 16-bit Bluetooth SIG assigned number for a Bluetooth SIG defined characteristic. Supported values are typically constrained by the service. See [assigned_numbers] for the list of SIG Assigned Numbers for GATT characteristic UUIDs.
Recorded Characteristic
The Recorded Characteristic field contains a partial or a complete characteristic value. The characteristic value is identified by the UUID field. For most UUID values, the definition of the corresponding characteristic value is included in this document.
E2E-CRC
If the service using the Blood Pressure Record characteristic supports E2E-CRC, the status of the recorded characteristic is secured by a CRC calculated over all fields of all parts of a multi-message record not including the E2E-CRC-field itself. See § crc_calculation for further information about the CRC calculation.
Guides on this site
The metric Blood Pressure Record carries, on every platform this site covers — each type quoted in its platform's own words:
No guide on this site names 0x2B36 yet. The connected-devices guides cover pairing, subscribing and testing for the device types they do name.
Questions
- What is the UUID of the Blood Pressure Record characteristic?
- 0x2B36. The Bluetooth SIG's characteristic_uuids.yaml lists Blood Pressure Record as 0x2B36 with the identifier org.bluetooth.characteristic.blood_pressure_record. No file in the SIG's repository ties it to a service: the repository lists service and characteristic UUIDs separately.
- Which Blood Pressure Record fields are optional?
- 1 of its 5 fields has a published size that can be zero: E2E-CRC (0 or 2; no “Present if” line in its text). Segmentation Header (1), Sequence Number (2) and UUID (2) have a fixed size. Recorded Characteristic (Variable) has a size that is not a plain number.
- In what order does the Blood Pressure Record structure list its fields?
- 1. Segmentation Header (boolean[8], 1, offset 0); 2. Sequence Number (uint16, 2, offset 1); 3. UUID (uint16, 2, offset 3); 4. Recorded Characteristic (Determined by UUID, Variable, offset 5); 5. E2E-CRC (uint16, 0 or 2). Sizes are as the SIG publishes them; an offset is given only where every earlier size is a plain number.
Source
Read on 2026-10-17 from gss/org.bluetooth.characteristic.blood_pressure_record.yaml and assigned_numbers/uuids/characteristic_uuids.yaml in the Bluetooth SIG’s public repository (branch main, commit 408f4a0, committed 2026-10-14), by scripts/fetch-bluetooth-gatt.mjs. The file’s notice says it is proprietary to Bluetooth SIG, that furnishing it grants no licence, and that it is subject to change without notice; it is © Bluetooth SIG, Inc., and its text is quoted here for identification. Generated by AIFitnessAPI, which is not affiliated with Bluetooth SIG; the SIG’s file remains the authority. The full notice and the conventions used on these pages are on the reference hub.