Seiko
Seiko Prospex Alpinist SPB121
39.5mm steel · Caliber 6R35
Not enough data yet.
No current price — check back once prices are tracked.
Not enough data yet
Not enough data
Fewer than 3 recent prices in this condition.
Not enough data yet
No current price.
No price history yet.
Too new to chart: not enough resale history yet.
Key takeaways
- Note: Not enough data yet. Only 2 Good-condition resale prices so far; scores need at least 10.
Real buy-in = (Price paid − Expected Good-condition resale) ÷ Months owned
Shown once this model has enough resale history.
Price paid defaults to today's price. Expected resale comes from how much of its launch price this model keeps over time, and is never more than what it sells for used today.
Real buy-in calculator
Available once there is enough resale history to estimate future value.
Costs less to own
Nothing among the watches we track costs less to own right now.
FAQs
What is the Seiko Prospex Alpinist SPB121 worth used?
There aren't enough recent Good-condition prices to give a range yet.
What does the Seiko Prospex Alpinist SPB121 really cost to own?
Not enough data yet. Only 2 Good-condition resale prices so far; scores need at least 10.
Should I buy the Seiko Prospex Alpinist SPB121 now or wait?
We don't have a current price to judge yet.
Report a price you paid, sold for or spotted
Updated Nov 15, 2026 · 2 data points · formula v1.2.0 · How scores work