Orlando Bloom with Mighty and (right) displaying his tribute tattoo.

Actor Orlando Bloom has had an ace of spades inside a heart inked under the name of his late dog Mighty, on his chest.

A week after his dog went missing, Bloom shared on Instagram on Wednesday that his dog is dead.

Paying a tribute to the pet he had welcomed into the family in 2017, he wrote: "Mighty's on the other side now. After seven days of searching from sunrise to sunset and into the wee hours, today, the 7th day - the number of completion - we found his collar."

"I have wept more this week than I thought possible, which has been very cathartic and healing."

Bloom wrote that he "left no stone unturned" in the search for Mighty, which included him crawling "thru all the man holes, under the roads, (searching) every back yard and creek bed".

"I feel so grateful to have learned from my little Mighty man that love is eternal and the true meaning of devotion," Bloom wrote.

"I feel sure he was looking down on me whistling in every back yard and knowing that I was doing all I possibly could to respect our bond. He was more than a companion. It was a soul connection for sure."

"I'm sorry. I love you," he continued. "Thank you. RIP my MIGHTY HEART".

Bloom concluded his post by thanking his community for its support, which allowed him to "see the best of people even in the worst of times".