Initially, Brown focused on cross-country running and middle-to-long distance track events. Despite competing at the national level, her physique led to frequent injuries, including stress fractures. In 2015, she transitioned to cycling, joining the St Kilda Cycling Club in Melbourne.

| Season | Event | Rank |
|---|---|---|
| 2021 | Women's Individual Time Trial | 4 |
| 2021 | Women's Road Race | 47 |
Brown made her professional debut at the 2018 Tour of California, finishing 38th. She has since achieved notable success. At the 2020 Tokyo Olympics, she narrowly missed a medal in the Women's Individual Time Trial, finishing fourth.
Brown secured silver medals in the time trial at the 2022 and 2023 Road World Championships. She also won gold in the road time trial at the 2022 Commonwealth Games in Birmingham.
In the UCI World Tour, Brown has consistently performed well. She achieved first-place finishes in 2021, 2023, and 2024. Additionally, she secured second place twice in the prestigious Liege-Bastogne-Liege one-day classic.
On 27 July 2024, Brown competed in the Women's Individual Time Trial at Pont Alexandre III. Representing Australia, she finished first among competitors from various countries including New Zealand, China, and Italy.
Cycling Australia named Brown Female Road Cyclist of the Year for three consecutive years (2020-2022). Her consistent performance has solidified her reputation as a top cyclist.
Brown resides in Italy with her husband Elliot. She holds a degree in International Studies and Politics from the University of Melbourne. Her family includes her parents Tony and Ruth, and siblings Hamish, Duncan, and Lachlan.
An all-rounder with a strong time trial focus, Brown often practises breathing and visualisation techniques before races. She believes in pushing herself to achieve her best performance each day.
Looking ahead, Brown aims to continue competing at high levels and securing more victories for Australia. Her dedication to cycling remains unwavering as she strives for excellence.
Grace Brown's journey from running to cycling exemplifies resilience and determination. Her achievements highlight her as a key figure in women's road cycling.Initially, Brown focused on cross-country running and middle-to-long distance track events. Despite competing at the national level, her physique led to frequent injuries, including stress fractures. In 2015, she transitioned to cycling, joining the St Kilda Cycling Club in Melbourne.