An idiom meaning to be on a completely different level or scale; far superior or of a different order of magnitude compared to something else.
彼の英語力は僕とは桁が違うから、通訳が必要ないことが多い。
His English ability is on a different level from mine, so he often doesn't need an interpreter.
この会社の売上はライバル企業とは桁が違う。
This company's sales are on a different scale compared to its rivals.
専門家から見れば、その選手の実力は桁が違うと評価されている。
Experts evaluate that the athlete's ability is on a different level.
新モデルの性能は旧モデルと桁が違うので、買い替えを決めた。
The performance of the new model is on a completely different level from the old one, so I decided to replace it.