Tan Hooi Ling grew up in Kuala Lumpur. She studied mechanical engineering at the University of Bath, graduating in 2006, and spent an industrial placement at Eli Lilly in Basingstoke. She then worked as a business analyst at McKinsey in Malaysia, which sponsored her MBA at Harvard Business School.
At Harvard she and Anthony Tan entered a business plan for a taxi booking app in the 2011 New Venture Competition and won second prize. MyTeksi launched in Malaysia in 2012. It became GrabTaxi in 2013 and Grab in 2016, when its headquarters moved to Singapore.
After her MBA she had to return to McKinsey to serve out the bond tied to its sponsorship. She later worked at Salesforce while still helping Grab, and went full time at Grab in 2015. She took the title of chief operating officer and focused on product, people operations and customer experience.
On May 25, 2023, Grab announced that she would step down from her operating roles and her seat on the board by the end of 2023. She moved into an advisory role. By then Grab had been on Nasdaq since December 2021.