We have very few certainties regarding the life of Wace. His date of birth is unknown, and attempts to estimate it have been based essentially on extrapolations from the dates of composition of his extant works. The nineteenth-century scholar Gaston Paris concluded that the poet must have been born around the year 1100, on the grounds that by the death of Henry I, in 1135, he had already completed his studies and was established as a ‘clerc lisant’. Anthony Holden, the editor of the Roman de Rou, inclines towards 1110. A date of birth in the first half of the first decade of the twelfth century would fit with the overall picture of the poet's production; though, as Glyn S. Burgess has pointed out, Wace was still active in the mid 1170s, making his career an unusually long one. His name, which also appears in the manuscripts as ‘Guace’ and ‘Gace’, is Germanic, possibly a diminutive form of Walter; it has survived to this day as a family name, including in Jersey. In the case of our poet, ‘Wace’ must have been his Christian name, as family names were not in common usage in the early twelfth century. References to ‘Robert Wace’ are erroneous, based on textual misreading.

What little information we have regarding Wace's long and productive life is contained in a few lines scattered in his Roman de Rou and a handful of legal documents. The poet was born on Jersey, was sent to school at Caen, on the Norman mainland, and pursued his studies in France before returning to Normandy, as he tells us himself in his Roman de Rou (Troisième Partie, 5305–12):

Who paid for these long studies away from home is unknown. Presumably it was his family, as an abbey was unlikely to invest such resources in a student (however promising) who was not destined to become a monk. In the event, Wace does not appear to have received more than minor orders.