The Teltonika protocol (canonically called Codec 8 and Codec 8 Extended) is the binary AVL wire format Teltonika GPS trackers use to report data. It is the industry reference for the mid-to-pro fleet tier · designed for high-throughput telemetry (50+ I/O channels per packet), efficient binary encoding (well under 100 bytes per record), and reliable offline buffering (tens of thousands of records held when GPRS is down).
The spec is published in full at wiki.teltonika-gps.com · this openness is why third-party servers (Traccar, Flespi, Traxelio, and Teltonika's own FOTA Web) can all decode the same stream.
Protocol-at-a-glance
- Transport · TCP
- Default port ·
5027(Traxelio's ingest port; configurable on the device side via configurator) - Encoding · binary AVL records, length-prefixed, big-endian
- Auth · IMEI handshake in first packet (length-prefixed UTF-8 string); server replies
0x01(accept) or0x00(reject) - Codec versions · Codec 8 (legacy, fully supported), Codec 8 Extended (current, supports >255 I/O element IDs)
- Other codecs · Codec 12 (commands), Codec 13 (NMEA), Codec 14 (configuration) ride alongside on the same connection
Packet structure (Codec 8 Extended)
[PREAMBLE = 0x00000000] [DATA_LENGTH] [CODEC_ID = 0x8E] [N_RECORDS]
[RECORD 1] [RECORD 2] ... [RECORD N]
[N_RECORDS] [CRC-16/IBM]
Each record:
[TIMESTAMP (8B, ms since epoch)] [PRIORITY (1B)]
[GPS: lon (4B) | lat (4B) | alt (2B) | angle (2B) | sats (1B) | speed (2B)]
[IO_EVENT_ID (2B)] [N_TOTAL_IO (2B)]
[N_1B_IO] [1B IO_ID + 1B value] × N
[N_2B_IO] [2B IO_ID + 2B value] × N
[N_4B_IO] [2B IO_ID + 4B value] × N
[N_8B_IO] [2B IO_ID + 8B value] × N
[N_XB_IO] [2B IO_ID + variable] × N # Extended codec only
The I/O element IDs are documented per device model · Teltonika maintains a master list at wiki.teltonika-gps.com/view/AVL_Data. Some examples: ID 16 = Total Odometer, ID 17 = Accelerometer X, ID 21 = GSM Signal, ID 66 = External Voltage, ID 67 = Battery Voltage, ID 200 = Sleep Mode.
Why Teltonika hardware ships this protocol
- Deep I/O · 50-200+ I/O elements per packet (vs ~10 in GT06, ~15 in H02) · fits CAN, OBD, sensor, and event channels in one record
- Codec 8 Extended · raised the I/O ID ceiling from 255 to 65535 · matters for FMC230 / FMM250 with rich CAN profiles
- Offline buffering · device holds 10,000+ records in flash · drains them on reconnect prefixed with a
priority=0flag - Bidirectional · Codec 12 commands flow server-to-device on the same TCP channel (no SMS round-trip needed for engine cut, server change, configuration push)
The trade-off vs the budget tier (GT06, H02, GPS103): Teltonika hardware costs 5-10x more per unit. For fleets where CAN bus depth, install quality, and 24-month warranty matter, that's the right trade.
Configuring a Teltonika device for Traxelio
Two paths · Teltonika Configurator (Windows desktop) or FOTA Web (over-the-air):
Configurator path (initial setup):
- Download Teltonika Configurator from wiki.teltonika-gps.com
- Connect via USB cable
- Open the GPRS section · set Domain to
traxelio.com, Port to5027, Protocol to TCP - Set Codec to
Codec 8 Extended(orCodec 8for older FMB1xx models) - Save to device · device reboots
- Confirm the first decoded position in Traxelio
FOTA Web path (already in your fleet):
- Log into fm.teltonika.lt (Teltonika's free OTA platform)
- Select your device by IMEI
- Configuration > Edit > GPRS section · set the new server endpoint
- Push configuration · device picks it up on next connection
The IMEI stays the same. The SIM stays the same. Only the destination server changes. No re-install.
Supported devices in our catalog
83+ devices declare protocol: "teltonika" · the headline models: FMB001 (OBD plug), FMB125 / FMB140 (wired pro fleet), FMC125 / FMC150 (4G LTE pro), FMC230 (heavy-vehicle CAN), FMM130 / FMM250 (compact 4G), FMT100 (asset tracker). The full Teltonika catalog is supported · any FMxxxx model with Codec 8 or Codec 8 Extended in its datasheet works.