Kioxia Holdings filed first-quarter results on Friday afternoon in Tokyo showing revenue up 415.5% year on year and profit up roughly forty-six-fold. It is the cleanest available read on whether AI storage demand is real volume or a price spike, because Kioxia is a near-pure-play NAND maker with a single reportable segment. Its own answer is: mostly price.

The numbers

Revenue ¥1,767,117 million against ¥342,799 million in the quarter ended June 2025. Operating profit ¥1,270,017 million against ¥44,899 million. Profit ¥842,171 million against ¥18,273 million. Basic EPS ¥1,539.91, up from ¥33.90. SSD and Storage contributed ¥1,174.7 billion, Smart Devices ¥525.7 billion. The equity ratio jumped from 37.9% to 50.8% in a single quarter. The board also approved a 3-for-1 stock split effective 1 October.

Why 415.5% is the wrong number to quote

The comparison quarter was the bottom of the last NAND downcycle — in it, Kioxia's own revenue was down 20.0%, operating profit down 64.3% and profit down 73.8%. Measuring from a trough produces a spectacular multiple that says little about momentum. The honest figure is +76% quarter on quarter, from ¥1,002.9 billion in the three months to March. And the growth is a repricing, not a volume event: the filing's own causal ordering is that revenue rose "primarily due to a significant increase in average selling prices (ASPs)... as well as an increase in bit shipment and the positive effect of exchange rates." Bits shipped comes third. A weaker yen — 160 to the dollar against 145 — accounts for roughly a tenth of the jump.

What is not an accounting trick

Worth stating, because a fivefold move invites suspicion: there were no changes to consolidation scope, accounting policies or estimates, and the statements carry a voluntary auditor review. The disclosed one-offs run against the headline — non-GAAP operating profit is higher than the IFRS figure, because the excluded items are charges, including a ¥36.6 billion litigation provision that appears for the first time.

One tell in the outlook

Subtract the quarter's actuals from the half-year guidance and the implied second quarter is exactly ¥2,390,000 million of revenue, exactly ¥1,890,000 million operating profit and exactly ¥1,270,000 million net. Round to the last five digits on every line. Kioxia has published actuals plus placeholders, and is paying no dividend on a record quarter.