SML decoder

Make telegrams from the meter's INFO interface readable

Electronic meters (eHZ, modern metering devices) continuously send telegrams in the Smart Message Language (SML) via their optical INFO interface. Paste a capture as hex: the decoder shows meter readings, power and identifiers with their OBIS code and checks the checksums.

SML data as hex (spaces and line breaks do not matter)

Open file (.bin / .hex)

🔒 The data stays in your browser – nothing is transmitted.

How to get the data

Attach a reading head: an optical reading head (IR, USB or Wi-Fi) is attached magnetically to the meter's INFO interface. Transmission usually runs at 9600 baud, 8N1.
Capture: record a few seconds so that at least one telegram is complete – e.g. with Tasmota (SML dump), vzlogger or on Linux with dd and hexdump. You can open binary files (.bin) directly.
Paste and decode: spaces, line breaks and 0x prefixes do not matter. With several telegrams the decoder shows the last complete one.

What the decoder can – and cannot – do

It reads unencrypted SML data as output by the INFO interface: active energy import and export (1.8.x / 2.8.x), power, voltage, current, frequency, phase angles, server ID with meter ID according to DIN 43863-5.
Instantaneous values missing? Many meters only output them after the PIN has been entered (extended data set). Your metering point operator provides the PIN.
The wired LMN between meter and smart meter gateway is TLS encrypted – no online decoder can read such captures. For development and testing on the LMN there are the LMN-Parser, the LMN-Tester and the LMN-USB12V adapter.
The display is a technical aid, not a reading relevant under calibration law – the meter's own display always prevails.

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