As of Q4'25 (2026-01-03), ONTO's P/E ratio has surged to 194.34, marking a dramatic increase from the previous quarter's value of 36.89. This latest data point represents the highest P/E ratio observed in the covered period. Throughout the period from Q1'23 to Q4'25, the P/E ratio exhibited significant volatility. After a steady rise from 20.19 in Q1'23 to a peak of 73.92 in Q1'24, the ratio declined to the low 20s by Q2'25, before spiking sharply in Q4'25. This pattern suggests periods of both rapid expansion and contraction in valuation, with the most notable inflection occurring in the final quarter.