Chai Keong Toh FREng (born 1965) is a Singaporean computer scientist, engineer, industry director, former VP/CTO and university professor.

Toh's current research is focused on Internet-of-Things (IoT), architectures, platforms, and applications behind the development of smart cities.

In 2014, Toh was appointed as Assistant Chief Executive (Engineering And Technology), of Infocomm Development Authority of Singapore (IDA) in 2014.

[17] He left Infocomm Media Development Authority (formerly known as IDA)[18] and joined Singapore Power Telecom Ltd as VP and CTO.

He is also listed among the top 20 authors[21] in Wireless/Mobile Networks in the world by THOMSON Essential Science Indicators (ESI) for technical papers published from 1995 to 2005.

[23][24] His first successful implementation of Wi-Fi Ad-Hoc Mode was achieved in 1998 when he established a working wireless ad hoc network in Georgia, USA.

[28] In 2011, he invented a method to identify witnesses during car accidents using a distributed information dissemination and data fusion approach.