The dollar index fell below 100 as traders sold the greenback after the Fed meeting, with USD/JPY sliding on rising BOJ hike and intervention risks and mixed signals for emerging markets and Bitcoin.

The U.S. Dollar Index (DXY) fell below the psychologically significant 100 level on Thursday, sliding 0.5% to 99.79 as markets digested the aftermath of Wednesday’s Federal Reserve meeting and recalibrated positions across currency markets. USD/JPY dropped 1% to 158.22, one of its sharpest single-session declines in weeks, as a combination of post-FOMC profit-taking, rising rate divergence expectations, and the looming prospect of Bank of Japan intervention weighed on the dollar against the yen.

The move is notable precisely because of its direction. As recently as last week, the DXY had broken back above 100 for the first time since late 2025, driven higher by safe-haven demand from the Iran conflict and inflation fears stemming from the Strait of Hormuz disruption. That rally had pushed USD/JPY as high as 159.40 during Tuesday’s Asian session. Thursday’s reversal therefore represents a meaningful technical breakdown, with the 100 level now flipping from support to resistance.

The Post-FOMC Paradox

The dollar’s weakness in the wake of a hawkish Fed statement appears counterintuitive on its surface — Powell raised the 2026 inflation forecast to 2.7%, signalled only one rate cut for the year, and explicitly cited the oil shock as a persistent inflationary risk. In a traditional macro framework, that combination should support the dollar. But currency markets have responded differently, focusing instead on three complicating factors.​

First, much of the hawkish repricing had already occurred in the days leading up to the FOMC meeting, with market expectations for Fed easing having compressed from two-to-three cuts earlier in the year to just one. With that narrative largely priced, the announcement became a sell-the-news event for dollar bulls who had positioned for upside. Second, Powell’s acknowledgement of heightened economic uncertainty — including the risk that the oil shock could simultaneously depress growth while keeping inflation elevated — raised fresh concerns about the dollar’s medium-term trajectory if the U.S. economy weakens while the Fed’s hands remain tied by inflation. Third, and critically, the divergence between the Fed and other major central banks is shifting.

The Bank of Japan held its policy rate unchanged at 0.75% on Thursday — its highest since September 1995 — but markets are pricing a rate increase to 1.00% by end-June. Mizuho Financial’s markets co-chief Kenya Koshimizu told Reuters in February that up to three BOJ hikes in 2026 are entirely possible. Japan’s Finance Minister has also stated explicitly that authorities stand ready to intervene in FX markets if yen weakness persists, with USD/JPY above 160 viewed as a potential trigger for BOJ action. Thursday’s 1% drop in USD/JPY, pulling the pair to 158.22, suggests markets are pre-empting that intervention risk.

The dollar’s stumble below 100 is also a signal to emerging markets and commodity-linked currencies. The Philippine peso breached the 60-per-dollar level on Thursday as oil costs weighed on the country’s import bill, while gold stabilised following a sharp 4% decline in the prior session. For crypto markets, a weaker dollar historically provides modest tailwind support — but with Bitcoin already down 4.62% to $71,313 on the day, macro headwinds from the Fed’s inflation posture are currently overwhelming any currency-driven relief.