Name: Grand Seiko 56GS 5645 / 5646
Brand: Grand Seiko

Typical asking price in Japan

¥238,000 ≈ US$1,500

Range ¥109,780–¥408,000 from 10 dealer listings, including Japan's 10% consumption tax. Checked 2026-11-02.

What it costs to bring home · Example listing 1 · Example listing 2

When was yours made?

This model uses Seiko movement 5645. Japanese listings often give the serial number or the year. Our Seiko date finder turns it into a production date.

Reading a Japanese listing for this watch

シリアル / 型番 shiriaru / kataban: Serial number / reference number (e.g. 5626-7040).
自動巻き / 手巻き jidōmaki / temaki: Automatic / manual wind.
ハイビート haibīto: Hi-Beat, a fast-beating movement (28,800 or 36,000 beats an hour).
亀戸製 / 諏訪製 Kameido-sei / Suwa-sei: Made at Daini Seikosha (Kameido, Tokyo) or Suwa Seikosha (Nagano), Seiko's two watch factories.
メダリオン medarion: The emblem on the caseback, e.g. the Grand Seiko lion or the King Seiko shield.
ファーストダイバー fāsuto daibā: Seiko's first diver, the 62MAS of 1965.
植村ダイバー Uemura daibā: The 6105-8110 diver, named after the explorer Naomi Uemura.
ツナ缶 tsuna-kan: 'Tuna can': Seiko's shrouded professional divers.

More in our guide to Japanese listing terms.

Where to look

Licensed shops that list Grand Seiko among their specialities:

Commit Ginza Ginza · ★ 4.9
Jack Road Nakano · ★ 4.3
Komehyo Shinjuku Shinjuku · ★ 4.9
Komehyo Nagoya Main Store Osu, Nagoya · ★ 4.2
Ginza Rasin Ginza · ★ 4.8
Komehyo Umeda Umeda · ★ 4.8

Related models

Prices are what Japanese dealers ask on their own websites, not auction or buyback prices. Condition, papers and dial variant can move a price a lot. See all models in the Japan price guide.