How to say "impeccable" in Japanese

• 申し分ないもうしぶんないCommon
  expression, i-adjectiveCovers 'impeccable' in the sense of perfect and completely satisfactory — conduct, work, or arrangements so good that nothing can be faulted. This is the form without の, identical in meaning to 申し分のない.
  今いまのところはすべて申し分もうしぶん無ない。↗

  Everything is fine so far.
• 申し分のないもうしぶんのないCommon
  expression, i-adjectiveThe same phrase with の inserted, for the same sense of 'impeccable': ideal and leaving nothing to be desired, whether for results, service, or behavior. Nothing separates it from 申し分ない, so choose by phrasing.
  散歩さんぽには申し分もうしぶんのない日ひだった。↗

  It was an ideal day for walking.

「申し分ない」 and 「申し分のない」 are the same expression, the latter simply adding の, so for 'impeccable' meaning perfect, flawless, or leaving nothing to be desired either works; the choice is phrasing, not sense.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• 申し分ないもうしぶんないperfect
• 申し分のないもうしぶんのないperfect
• 非の打ち所のないひのうちどころのないimpeccable
• 一分の隙もないいちぶのすきもないwithout any weak spot
• 非の打ち所がないひのうちどころがないfaultless