Seiko 5 Sports GMT vs Steinhart Ocean One

Side-by-side comparison of specifications and features

Seiko5 Sports GMT

SSK001

SteinhartOcean One

Ocean One

Key Differences

Best Value

Seiko 5 Sports GMT (SSK001)

Starting from $400

Best Water Resistance

Steinhart Ocean One (42mm)

300m (3x more)

Price Comparison

Seiko 5 Sports GMT

MSRP

$400

New

$570

Used

$264

Steinhart Ocean One

MSRP

$750

New

$955

Used

$450

MSRP New (Amazon) Used (eBay)

Comparison of Seiko 5 Sports GMT, Steinhart Ocean One
Specification	Seiko 5 Sports GMT	Steinhart Ocean One
Pricing
MSRP	$400	$750
New Price	$570	$955
Used Price (Low)	$264	$450
Used Price (High)	$1,023	$1,495
30-Day Trend	↑ +3.2%	↑ +0.3%
Used Price Range	$264 - $1,023	$450 - $1,495
Identity
Reference	SSK001	Ocean One
Nickname	N/A	N/A
Style	Sports, Tool	Diver, Tool
Release Era	2020s	2000s
Dimensions
Diameter	42.5mm	42mm
Thickness	N/A	N/A
Lug Width	N/A	N/A
Lug to Lug	N/A	N/A
Movement
Movement	Automatic	Automatic
Power Reserve / Battery	N/A	N/A
Accuracy	N/A	N/A
Case
Case Material	Stainless Steel	Stainless Steel
Crystal	Hardlex	Sapphire Crystal
Water Resistance	100m (recreational diving)	300m (diving)
Bezel	Bidirectional 24-hour	Unidirectional rotating
Dial
Dial Color	Black	Black/Blue
Luminous	Yes	Yes
Community
Review Rating	N/A	N/A
In Collections	N/A	N/A
On Wishlists	N/A	N/A
Forum Threads	N/A	N/A

Quick Summary

Seiko 5 Sports GMT and Steinhart Ocean One can look close on a spec sheet, yet the tradeoffs that matter most are usually water-ready utility versus dressier everyday wear, sports character versus diver versatility. They both touch the tool use case, so smaller spec differences can matter more than brand preference.

How to choose

The biggest practical difference is usually movement and upkeep. Start with wrist fit and movement preference, then use water resistance and price to break the tie.

Seiko 5 Sports GMT

Seiko 5 Sports GMT is a better fit for mechanical-watch enthusiasts, sports styling.

Steinhart Ocean One

Steinhart Ocean One is a better fit for mechanical-watch enthusiasts, diver styling.

Key Differences

Movement and upkeep

Seiko 5 Sports GMT: automatic movement

Steinhart Ocean One: automatic movement

Both use the same movement type, so maintenance differences are limited and fit or feature details should decide the purchase.

Size and wearability

Seiko 5 Sports GMT: 42.5mm

Steinhart Ocean One: 42mm

Their size profiles are relatively close, so fit comes down to shape, weight, and how each watch sits on your wrist.

Water resistance

Seiko 5 Sports GMT: 100m

Steinhart Ocean One: 300m

Water resistance is a meaningful separator here — the higher-rated option gives more flexibility for swimming or rougher daily use.

Price and value

Seiko 5 Sports GMT: $400

Steinhart Ocean One: $600

There is a real price gap here — treat the more expensive option as an upgrade decision and confirm whether the extra spend buys something you will notice in weekly use.

Style and use case

Seiko 5 Sports GMT: sports

Steinhart Ocean One: diver

Seiko 5 Sports GMT leans more sports, while Steinhart Ocean One pulls toward diver use case — pick the one that matches how you will actually wear it.

Crystal and materials

Seiko 5 Sports GMT: Hardlex crystal · steel

Steinhart Ocean One: sapphire crystal · steel

Crystal choice can change long-term wear expectations — one may prioritize scratch resistance while the other keeps cost or vintage feel in check.

Choose Seiko 5 Sports GMT If...

You are specifically shopping for a sports style watch.
You want the lower current entry price.

Choose Steinhart Ocean One If...

Swimming, beach use, or tougher daily wear is part of the plan.
You are specifically shopping for a diver style watch.
You are comfortable paying more for a stronger feature set.

Price and Value Notes

Seiko 5 Sports GMT is often the value play at current pricing, while Steinhart Ocean One makes more sense if you will use its extra features regularly.

There is a real price gap here — treat the more expensive option as an upgrade decision and confirm whether the extra spend buys something you will notice in weekly use.

Where to Check Deals

Check current deals on Amazon and eBay using the buttons below — listing prices, seller quality, and condition can change quickly.

Check current deals on Amazon and eBay

Prices change often, so compare the latest listings and condition options before you buy.

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Seiko 5 Sports GMT

Check Price on AmazonOpens in new tab · Price may vary

Check Price on eBayFrom $387 · Live listings

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Steinhart Ocean One

Check Price on AmazonOpens in new tab · Price may vary

Check Price on eBayFrom $600 · Live listings

Affiliate links — WatchCompared earns a commission on qualifying purchases. This doesn't affect your price.

Comparison FAQ

Which one is better for smaller wrists?

Neither is clearly smaller: case width is 42.5mm vs 42mm. Pick on strap and looks instead — the size difference is not what will decide this for you.

Which is better for swimming or rough daily wear?

Steinhart Ocean One — it is rated 300m versus 100m. Both are in the same broad bracket, so treat this as a tiebreaker rather than a deciding factor.

Is the more expensive one worth it?

Seiko 5 Sports GMT is the value pick at roughly $200 less. Pay more only if a specific difference above matters to you — otherwise the cheaper one is the smarter buy. Confirm live listings, since marketplace pricing moves.