The earthquake went on for minutes. First it was slow and rolling, then suddenly strong. My house is still moving slightly.
The epicenter was Tokyo prefecture, technically, but near Ogasawara, which are islands pretty far off the coast.
On the Japanese Shindo scale of 1-7 it was a 5+ at the epicenter. Shindo 4 where I live.
The magnitude was 8.5, but very deep – 590 km.
No damage in my house. Just a lot of shaking. No tsunami warning.
A separate earthquake woke me up at 1:06 am.