Leicester Cathedral also confirmed that the coffin to be used to re-bury the 15th century ruler will be made by one his sister's direct descendants.
Dean of Leicester David Monteith said that the cost of the project had been finalised at £2.5 million.
The approved tomb, which has been accepted by the Cathedral Fabrics Commission for England, features a large block of Swaledale stone with a deeply incised cross, above a dark plinth of Kilkenny stone, carved with King Richard's name, dates, motto and coat of arms.
Unveiling images of the King's final resting place, the Dean said: "This is a tomb which reflects the era in which it is designed as well as the solemn purpose for which it is commissioned.
"To do anything else would be a pastiche of a medieval tomb and would ignore the fact he is being reburied in the 21st century."
The coffin will be built by cabinet-maker Michael Ibsen, a direct descendent of Richard III's sister, Anne.
The Diocese of Leicester will contribute £500,000 to the total project budget and private donations are also being sought.
The king's remains were discovered under a car park in Leicester in 2012.