Side-by-side cruise ship comparison · Updated February 2026
.jpg%26w%3D400&w=3840&q=75)
across 5 categories
Size
Based on gross tonnage and length
Capacity
Based on passengers and crew
Modernity
Based on year built
Service
Based on passenger-to-crew ratio (lower is better)
Spaciousness
Based on gross tonnage per passenger (higher is better)
Costa Diadema
Costa Firenze
Gross Tonnage
Costa Diadema
132,500 GT
Costa Firenze
135,225 GT
Length
Costa Diadema
306 m
Costa Firenze
323 m
Beam
Costa Diadema
37 m
Costa Firenze
37 m
Passengers
Costa Diadema
3,724
Costa Firenze
4,232
Crew
Costa Diadema
1,253
Costa Firenze
1,400
Decks
Costa Diadema
—
Costa Firenze
—
Year Built
Costa Diadema
2,014
Costa Firenze
2,021
Space Ratio
Costa Diadema
35.6 GT/pax
Costa Firenze
31.9 GT/pax
Passenger:Crew Ratio
Costa Diadema
2.97 :1
Costa Firenze
3.02 :1
| Specification | Costa Diadema | Costa Firenze |
|---|---|---|
| Overview | ||
| Cruise Line | Costa Cruises | Costa Cruises |
| Class | Diadema Class | Venezia Class |
| Status | active | active |
| Year Built | 2,014 | 2,021Winner |
| Dimensions | ||
| Gross Tonnage | 132,500 GT | 135,225 GTWinner |
| Length | 306 m | 323 mWinner |
| Beam | 37 m | 37 m |
| Draft | ||
| Capacity | ||
| Passengers | 3,724 | 4,232Winner |
| Crew | 1,253 | 1,400Winner |
| Key Ratios | ||
| Space Ratio | 35.6 GT/paxWinner | 31.9 GT/pax |
| Passenger:Crew Ratio | 2.97:1Winner | 3.02:1 |
| Build | ||
| Builder | Fincantieri | Fincantieri |
| Flag | Italy | Italy |
| IMO Number | 9636588 | 9765470 |
Costa Diadema offers more personal space with a space ratio of 35.6 GT per passenger versus 31.9. Built in 2021, Costa Firenze is 7 years newer — an advantage for travellers seeking modern amenities and design.
| Category | Winner |
|---|---|
| Size | Costa Firenze |
| Capacity | Costa Firenze |
| Modernity | Costa Firenze |
| Service | Costa Diadema |
| Spaciousness | Costa Diadema |
Bottom line: Costa Firenze wins more categories (3 vs 2), making it the stronger all-round choice based on current data.
Costa Diadema
Large 3,724-guest capacity offers competitive pricing
Well-suited for cruise newcomers
3,724 passengers means tons of activities
Comfortable atmosphere for two
Costa Firenze
Built in 2021 with modern facilities — great for a first cruise
Large 4,232-guest capacity offers competitive pricing
4,232 passengers means tons of activities
Comfortable atmosphere for two
Free cancellation on most rooms
Bundle & save on your cruise trip
Medical, trip cancellation & luggage cover
We may earn a commission from partner bookings at no extra cost to you.
— |
| Decks | — | — |
_in_Venice.jpg%26w%3D400&w=3840&q=75)
.jpg%26w%3D400&w=3840&q=75)
.jpg%26w%3D400&w=3840&q=75)