Sparkplug B and MQTT payload decoding

MQTT Viewer decodes Sparkplug B, Base64 and Hex payloads, formats JSON, and shows image payloads as images.

A Sparkplug B payload decoded into JSON in the topic panel, with the codec selector showing the chosen decoder

Sparkplug B

Payloads on spBv1.0/ and spAv1.0/ topics decode into their metrics, timestamps and sequence numbers. Decoded output is JSON, so it diffs and charts like any other payload.

Base64, Hex and images

Pick Base64 or Hex from the codec selector to decode a payload in place. PNG, JPEG, GIF, WebP and BMP payloads are shown as images.

The free online payload decoder does the same job in the browser.

An image payload rendered as a picture in the topic panel

Frequently asked questions

Does MQTT Viewer decode Sparkplug B?

Sparkplug B and Sparkplug A payloads decode into readable JSON.

Related features

MQTT Viewer is free and open source, and runs on macOS, Windows and Linux.

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