VPS/VDS with unlimited traffic

"Unlimited traffic" on a plan almost never means "as much as you like". It means the host doesn't count gigabytes but limits you through port speed and fair-use rules. Once you understand these two limits, it's easy to tell genuine unlimited from the marketing kind.

Port speed is your real limit

Physically, you can't push more through a port in a month than its bandwidth allows. Simple arithmetic at 24/7 load:

• a 100 Mbps port — about 32 TB a month;
• a 1 Gbps port — about 320 TB a month;
• a 10 Gbps port — petabytes in theory, but nobody loads it like that.

That's why unlimited at 100 Mbps is more honest than "1 Gbps and 1 TB of traffic": in the first case you know the ceiling, in the second, once you hit the cap, the speed may be cut to 10 Mbps or you'll be billed for every gigabyte. Also check whether the speed is guaranteed or "up to": on a shared port several customers split the channel, and in the evening the real speed is lower. Plans with a wide channel are collected on the 1 Gbps VPS and 10 Gbps VPS pages.

Fair use

Almost every unlimited contract has a fair-use clause. The wording varies, but the meaning is the same: if the server keeps the port 100% loaded for months, the host has the right to lower the speed, move you to another plan or ask you to leave. Read the terms before paying and look for specifics:

• whether there's an average-load threshold beyond which the speed is cut;
• whether only outgoing traffic is counted or incoming too (usually only outgoing);
• which kinds of load are prohibited: torrents, public proxies, file distribution, streaming.

When traffic really matters

1. A corporate VPN. Video calls, file exchange and backups through the tunnel add up to many gigabytes per employee. A small team easily uses 1–3 TB a month, so for a VPN VPS unlimited or a large allowance is almost a must.
2. File and media distribution. A video site, a file-sharing service, a distribution mirror, an update server for an app.
3. Backups. The first full upload and regular copies of large volumes eat traffic faster than you'd think. For a backup server, unlimited removes the question of overage charges.
4. Scraping and crawlers that download millions of pages.

An ordinary website, bot or database, on the other hand, will be fine with 1 TB: even a busy project rarely serves more than a few hundred gigabytes a month.

How to check the channel after purchase

Run iperf3 against a public server or download a large test file at different times of day. See whether the speed holds in the evening. To track traffic, install vnstat — it shows actual usage and helps you understand whether you need unlimited at all. The table above marks plans where unlimited traffic is stated on the host's website; check the port speed in the specifications of the particular plan.