[SIGFOX] How many bytes can I transmit in one message to my device? You can send up to 8 bytes per message to the device (downlink). Last Update: August 8, 2017 December 5, 2016 2088 SIGFOX Q&A Downlink , Sigfox , Transmit Related Knowledge Base Posts -[SIGFOX] What is the advantage of using the Radiocrafts RC16xxxx-SIG module?[SIGFOX] Can I build a SIGFOX receiver or base station myself?[SIGFOX] Is my data secure and protected?