Bandwidth (also called data transfer) is the total amount of data your website can send to visitors in a given period — usually per month. Every time someone visits your site, your pages, images, scripts, and other files are transferred from the server to their browser. All of that counts against your bandwidth allowance.
How to Calculate Your Bandwidth Needs
Use this simple formula:
Monthly Bandwidth = Average Page Size × Monthly Pageviews × Redundancy Factor (1.5)
For example: If your average page is 2MB and you get 10,000 visits/month (assuming 2 pages per visit = 20,000 pageviews):
2MB × 20,000 × 1.5 = 60,000MB = ~60GB/month
What's a "Normal" Amount?
| Site Type | Typical Monthly Bandwidth |
|---|---|
| Personal blog (light traffic) | 1–10 GB |
| Small business site | 10–50 GB |
| Active blog / media site | 50–200 GB |
| E-commerce store | 100–500 GB |
| High-traffic web app | 500GB+ |
Unlimited Bandwidth — What Does It Really Mean?
Most shared hosts advertise "unlimited" bandwidth, but this is subject to fair-use policies buried in the terms of service. If your site consumes an unusually high share of server resources, your host may throttle you or ask you to upgrade. Always read the acceptable use policy before assuming unlimited means truly unlimited.
What Happens If You Exceed Your Bandwidth?
Depending on your host, you may face automatic overage charges (typically $0.01–$0.10 per GB over your limit), your site may be temporarily suspended, or you may simply be asked to upgrade your plan. Know your host's policy before you hit the ceiling.