Is the Voom internet on Royal Caribbean cruise ships really as fast as they say?

The "fastest internet at sea" isn't as fast you might hope.

As I found during a recent speed test, Royal Caribbean's Voom internet service, which the line touts as the fastest internet service in the cruise industry, is still far slower than what you're probably used to at home.

But the service still is a lot faster than internet service on cruise ships used to be just a few years ago. And it is, indeed, faster than what many of Royal Caribbean's competitors offer.

I put Royal Caribbean's Voom internet service to the test on board the line's 3,114-passenger Adventure of the Seas last week as it restarted departures in North America for the first time in 15 months. The ship was sailing from Nassau in the Bahamas to the line's private island in the Bahamas, Perfect Day at CocoCay, and Cozumel, Mexico.

Unveiled in 2001, Adventure of the Seas is the seventh-oldest of Royal Caribbean's 25 vessels, and -- as I'll explain below -- that's a factor in the internet speeds it's able to offer.

Royal Caribean's Voom internet service doesn't operate at the same speed on every one of the line's vessels. In general, Royal Caribbean's newer ships have faster internet speeds.

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How internet works on cruise ships

I'll get to the results of my speed test on Adventure of the Seas in a moment. But first, a little primer on cruise ship internet.

If you haven't cruised before, you may be surprised to learn that internet on ships generally is not free, as it is at many comparable resorts on land. Indeed, it's often quite expensive -- more than $20 a day on some lines. You easily can spend more than $100 a week on internet services when on a ship just to hook up one device. You'll pay even more if you want to have multiple devices online at the same time.

Internet on cruise ships also generally is far slower than what you've experienced on land. Where I live in North Carolina, the local cable company's least-expensive internet package promises download speeds of 200 megabits per second (Mbps) -- and the company, Spectrum, actually delivers a bit more than that to our location. You can pay just $20 more a month and get 400 Mbps, which is truly fast.

On a cruise ship, you'll be lucky to get download speeds of 5 Mbps.

Before you rail against the cruise lines about the cost and speed of what they offer, know that they're doing their best. They know you want fast internet on ships like you have at home, at an affordable price, and they are trying everything they can to make internet at sea faster and less expensive. On that front, they've made great strides in recent years.

But the bottom line is delivering fast and inexpensive internet to people on ships that are on the move in the open ocean is neither easy nor inexpensive. Remember that there are no high-speed cable lines reaching out to moving cruise ships, or line-of-sight transmitters that can reach them (except when they are close to ports). When you're getting internet on a cruise ship, you're getting it via a very expensive satellite system that's designed to be compatible with a moving target like a cruise ship that may be traveling at 20 miles per hour or more through bouncing waves.

When you think about it that way, it's really quite astounding we get internet at all when at sea.

Royal Caribbean's Voom service at a glance

Royal Caribbean offers two versions of its Voom internet service on ships:

• Surf is a less expensive service designed for general internet browsing and checking email but does not support streaming.
• Surf + Stream is a more expensive service that's touted as fast enough to stream movies and music and do many of the other things you would normally do over the internet.

What does Royal Caribbean's Voom internet service cost?

Rates for Royal Caribbean's Voom internet service seem to be always changing. But on my Adventure of the Seas sailing, the basic Surf service cost $17.99 per day for a single device when booked on board. The upgraded Surf + Stream service cost $22.99 per day.

The rates above are per day based on buying the service for the entire cruise. You can't get these rates if you just want internet access for a single day. My Adventure of the Seas sailing was seven nights in length, so the $22.99 per day cost of the faster service worked out to $160.93 for a single device for someone who booked it on the first day of the cruise for the entire trip.

Note that if you wait a few days after boarding to buy the internet service, you just pay for the remaining days of the voyage. In addition, at certain status levels in Royal Caribbean's loyalty program, the Crown & Anchor Society, you can get a discount on the packages.

You also often can buy a single-day pass for Voom on board at a significantly higher per-day cost than the multiday rate above. On my sailing, a single day (24-hour) pass was $25.99 for the slower Surf service and $32.99 for the higher-speed Surf + Stream service.

The above rates apply to those buying internet service on board. But that's not necessarily the best way to do it. One way to save considerably when buying internet service for a Royal Caribbean cruise is to buy it in advance of your sailing through the line's website. That's what I did, and I saved more than $30 for a week-long Surf + Stream package.

I paid just $128.73 for a week-long Surf + Stream package by booking it in advance on the Royal Caribbean website. That works out to $18.39 per day -- a 20% discount from the onboard cost.

You'll find a place to purchase internet and other services for your sailing on a Royal Caribbean cruise at the Royal Caribbean website. You'll have to create an account at the website and log in to reach the "cruise planner" section for your sailing to purchase such services.

How fast is Royal Caribbean's Voom internet service?

As noted above, I purchased the faster of Royal Caribbean's two Voom internet options, the Surf + Stream service, so that's the only one I was able to test.

I ran speed tests many times during the sailing, at different times, using the website speedtest.net both on my laptop and on an iPhone. What I found was that the Surf + Stream service usually offered download speeds of just around 3 Mbps. The upload speeds typically were around half that amount. But it varied at times.

Here, a speed test I conducted at 11 a.m. on June 14 when Adventure of the Seas was docked at Royal Caribbean's private island, Perfect Day at CocoCay.

Below is another speed test I did later the same day after Adventure of the Seas had departed Perfect Day at CocoCay and was sailing in the open ocean on its way to Cozumel, Mexico.

As you can see, both the download and upload speeds for the Voom internet on Adventure of the Seas at this point were slightly better than they were a few hours earlier. But they still were in the same basic range.

At no time during the cruise did I find download speeds exceeding 4 Mbps. But at times I found the download speed dropped as low as 1.5 Mbps.

Here is a speed test that I conducted at 9 p.m. on June 13 as Adventure of the Seas was in the open ocean near the Bahamas.

In comparison to internet speeds at resorts on land, the speeds I measured above may seem excruciatingly slow. But I found the Surf + Stream service on Adventure of the Seas did allow me to stream movies, as promised. I was able to continue my recent binge-watching of "Downton Abbey" on Netflix (hey, no judgment!) at bedtime on most nights.

There were a few hiccups, however.

On two nights of the cruise, I lost the internet connection completely for a spell. The second time this happened, toward the end of the cruise as we were sailing between Cozumel, Mexico, and the Bahamas, it was down for many hours. I also found the "Downton Abbey" drama with the lords and ladies Grantham got a little grainy at times, and I had a few buffering issues one night.

Netflix says the minimum speed required to stream is 0.5 Mbps. Netflix recommends 3 Mbps for standard definition streaming and 5 Mbps for high-definition streaming.

But, in general, Voom's streaming promise was met -- particularly in the one area where I really needed it to count. I was able to participate in an important, 45-minute staff meeting on Zoom while the ship was docked at Perfect Day at CocoCay.

Factors affecting Voom speed

Royal Caribbean's Voom service is generally faster on the line's newer vessels, which were wired from the beginning with higher-speed internet in mind. These would include the new Quantum Class and Oasis Class ships.

It's also faster on some older Royal Caribbean ships that have undergone "Royal Amplified" overhauls in dry dock that have included upgrades to the internet systems.

Royal Caribbean's Voom speed also can be affected by where a ship is located at any given time, and also by the weather -- both factors that can affect the connection to satellites.

Bottom line

If you're new to cruising, you might find yourself shocked at the price for internet on a Royal Caribbean ship. On a per-day basis, Royal Caribbean's fastest Surf + Stream service is about 10 times more expensive than the typical cable internet service in the United States. You also may be shocked by the slow speed of the service. At around 200 Mbps, my $60-a-month cable service at home in North Carolina, for instance, is about 65 times faster than what I experienced on Adventure of the Seas -- quite a difference!

That said, for a cruise ship, the Voom service on Adventure of the Seas and other Royal Caribbean ships actually is quite fast. And it lived up to its billing as a service fast enough to let you watch Netflix movies and shows at sea.

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