The post prompted fans to not only urge Chandler, 22, to pop the question but wonder if it had already been done.
Powell left a heartwarming response to the photo also, writing, "This made my entire day. I love you so much. Thank you for being the kindest most amazing girl a guy could ask for."
A very excited fan wrote, "Pop the question Chandler!!!" while another agreed: "PUT A RING ON IT, CHANDLER."
Another commenter wrote: "Am I the only one who gets excited every time they post thinking it's an engagement."
However, despite their loved-up relationship and the fans encouragement to marry, the pair have both stated previously that they are in no rush to get married just yet.
In December, they appeared on PEOPLE magazines cover, addressing engagement rumours at the time.
"For us at the moment, I think it's just been about enjoying life."
Chandler, who is an American wakeboarder, added: "It's really great just to slow down and enjoy the ride."
Bindi and Chandler first met at Australia Zoo in 2013. Now, they both dedicate their time to carrying on Bindi's father Steve Irwin's legacy through the Irwin family's Wildlife Warriors initiative.
In fact, Bindi's brother Robert Irwin recently channeled his father with an emotional throwback photo tribute on social media.
The 15-year-old took to Instagram to share a split image of two photos— one of the late Crocodile Hunter and one of himself feeding the massive aquatic reptile as it leaps in the air, reaching for food.
"Dad and me feeding Murray... same place, same croc - two photos 15 years apart ❤️🐊," he captioned the photo.