1Double; twice as much. Commonly used in expressions like "2倍" (twice) or "〜の倍" (double of ...).
今年の売上は去年の倍になった。
This year's sales have doubled compared to last year's.
彼は私の倍の身長がある。
He is twice my height.
二人分を頼んだので、料理の量が倍になった。
We ordered for two, so the amount of food doubled.
2A counter meaning "-fold" or "times," used to state how many times larger or smaller something is (e.g., 3-fold, 10-fold).
値段が3倍になってしまった。
The price has become three times as much.
この新しい製品は従来品より処理速度が5倍速いと宣伝している。
This new product is advertised as processing five times faster than the previous model.
データ容量は10倍に増加した。
The data capacity increased tenfold.
3Used to express odds or probability as "1 in n," e.g., 40倍 meaning odds of 1 in 40.
このくじの当選確率は40倍、つまり40分の1だ。
The winning odds for this lottery are 40 to 1, that is, 1/40.
この試験の倍率は100倍近くになっているそうだ。
I hear the odds for this exam are close to 100 to 1.