It works in the same way on board ships with Seafy Wi-Fi: you connect to the network and, before getting full Internet access, a portal appears where you can choose and purchase a package.

👉 In this article, we explain in a simple way what a captive portal is, why it’s used on ships, and how the Seafy portal works.

What is a captive portal (explained simply)

A captive portal is a web page that automatically appears when you connect to a public Wi-Fi network.

✅ show rules and terms (privacy, usage, etc.)

✅ allow user registration

✅ block Internet access until you take an action, such as purchasing a package

In short: you connect to Wi-Fi, but the Internet is “blocked” until you go through the portal.

Why it’s needed on ships (and why mobile data doesn’t work)

In open sea, mobile data often doesn’t work because the signal comes from the coast and has a limited range.

That’s why ships use a different system: satellite antennas, which can provide Internet even far from land.

This technology is much more complex than “normal” Wi-Fi, so it’s normal for packages to have a cost: bringing Internet to the sea is a real technical challenge.

How Seafy Wi-Fi works on board

The process is very simple:

1 - Turn on Wi-Fi on your phone

2 - Connect to the network called “Seafy”

3 - The Seafy portal (captive portal) opens automatically

- If it doesn’t open, just visit portal.seafy.com

4 - On the portal you can:

- log in / register

- view available packages

- purchase and activate your package

After purchase, you can browse the Internet for the amount of data included.

👉 Important: even without a package, you can always access the Seafy portal to choose and buy an offer.

How much data do you use? (and which package to choose)

Many people buy a package “at random” and then run out of data quickly.

✅ Chat and messaging

• WhatsApp / Telegram (text only): very few MB
• ideal if you just need to say “I’ll arrive soon” or message family

👉 A small package is enough.

✅ Social media (Instagram, Facebook, TikTok)

It depends: if you watch many stories and videos, data usage increases fast.

1 hour of social media with videos: up to 700–800 MB

👉 A medium package is better, especially if you use social media often.

✅ Video (YouTube, streaming)

This is the most data-consuming activity.

• 1 hour of YouTube in HD (720p): about 2 GB
• in Full HD (1080p): about 3 GB

👉 If you want to watch videos, you’ll need a larger package.

💡 Tip: lower the quality to 480p to use much less data.

Conclusion + CTA

Now you know what a captive portal is and why it works this way on a ship: first you access the Seafy portal, then you choose and activate the Internet package that best suits you.

📌 So, next time you’re on board:

✅ connect your phone to Seafy Wi-Fi

✅ open the Seafy portal

✅ choose the package based on what you want to do (chat, social or video)

✅ browse stress-free, even far from the coast