Moore struck a chord with locked-down Britain by walking around his garden with the help of a frame to raise 38.9 million pounds ($A70 million) for the National Health Service.
His endeavour and wit spread joy amid the grim news of the coronavirus outbreak: Moore's message to the world was that the sun would shine again and the clouds would clear.
"It is with great sadness that we announce the death of our dear father, Captain Sir Tom Moore," his daughters said in a statement following his death on Tuesday morning at Bedford Hospital in central England.
Over the past five years, he had been receiving treatment for prostate and skin cancer, his family said.
He was fighting pneumonia and was taken to hospital after testing positive for COVID-19 on January 22, unable to be vaccinated due to the other medication he was taking.
British Prime Minister Boris Johnson and Queen Elizabeth led the tributes to Moore, whose exploits won global admiration.
"Captain Tom Moore was a hero in the truest sense of the word," said Johnson, who spoke to Moore's daughter Hannah to pass on his condolences.
He became not just a national inspiration but a beacon of hope for the world.
The flag above his Downing Street office was lowered to half-mast in Moore's honour.
The queen, who knighted Moore at Windsor Castle last summer in recognition of his efforts, will send a message of private condolence to the family, Buckingham Palace said, adding the 94-year-old monarch had "very much enjoyed meeting Captain Sir Tom".
"Her thoughts, and those of the Royal Family, are with them, recognising the inspiration he provided for the whole nation and others across the world," the Palace said.
The White House also paid tribute to a man "who inspired millions through his life and his actions".
When Moore, dressed in a blazer and tie, started his sponsored walk at his home in the village of Marston Moretaine, 80km north of London, he hoped to raise a thousand pounds.
Instead, he amassed a world record sum for the National Health Service, with his quiet determination and cheerful outlook winning the hearts of the British public.
"The last year of our father's life was nothing short of remarkable. He was rejuvenated and experienced things he'd only ever dreamed of," his daughters said.
Whilst he'd been in so many hearts for just a short time, he was an incredible father and grandfather, and he will stay alive in our hearts forever.
Such was his fame that his 100th birthday was marked by a message from Johnson, a promotion to the rank of colonel and flypasts by both historic planes and modern RAF helicopters above his home.
He received more than 125,000 birthday cards from well-wishers around the world and became the oldest person to reach number one in Britain's main music singles chart, featuring on a cover version of You'll Never Walk Alone.
"I never, ever anticipated ever in my life anything like this, it really is amazing," Moore said when he turned 100 on April 30.
"Thank you very much to everyone, wherever you are."
Raised in Yorkshire, Moore served in India, Burma and Sumatra during WWII.