expression, adverb, noun which may take the genitive case particle 'no', noun
as much as possible; to the fullest extent
Used adverbially or adjectivally to express doing something to the maximum extent possible. Often followed by verbs like 努力する, 早く, or 多く.
できる限り早く返事をください。
Please reply as soon as possible.
できる限りのことはしました。
I did everything I could.
Phrase composed of できる (potential form of する, 'to be able to do') + 限り ('limit, extent'). Literally 'to the extent one can'.