Website Bandwidth Usage Calculator

Hosting plans often say "unmetered bandwidth" — then hit you with fair-use limits or overage fees anyway. This calculator tells you the actual monthly data transfer your site generates, so you can choose a plan that genuinely covers it.

Calculate monthly bandwidth

How this is calculated

Bandwidth is the total amount of data your server sends to visitors over a month. It's the sum of every page load, every image, every download, and every email attachment. Most hosts measure it in GB per month.

// Page bandwidth (GB) pageBandwidth = (pageSizeKB × pageviews) / 1,048,576 // Add media and downloads mediaBandwidth = (mediaMB + downloadsMB) / 1024 // Total totalGB = pageBandwidth + mediaBandwidth

The tricky part is page size. Most sites underestimate it. A typical WordPress page with images, scripts, and fonts is 1.5–2.5 MB. If you're running a page builder with uncompressed images, it can be 4–6 MB. Measure your actual average page size in Chrome DevTools → Network → "Transferred" total, not just the HTML size.

Media files are the wildcard. If you serve video or large images directly from your server, they can dwarf page bandwidth. A single 50 MB video watched 100 times is 5 GB — the same as 2,500 page views of a 2 MB page.

Worked example: A photo blog

A photographer's blog gets 50,000 monthly page views. Each page loads 4–6 full-size portfolio images, so the average page size is 3.5 MB (not 2 MB — photography sites are image-heavy). They also host a downloadable print catalogue (25 MB PDF) that gets about 200 downloads/month.

  • Page bandwidth: (3,500 KB × 50,000) / 1,048,576 = 167 GB
  • Catalogue downloads: (25 MB × 200) / 1024 = 4.9 GB
  • Total: ~172 GB/month

Most "unlimited" shared plans have a soft limit around 50–100 GB. This site would trigger a warning, and the host would ask them to upgrade or move the images to a CDN. Serving those images through Cloudflare or Bunny CDN would cut the origin bandwidth to under 20 GB — because the CDN caches and serves the files, not the origin server.

What counts as "normal" bandwidth?

Site typeMonthly pageviewsTypical bandwidth
Personal blog (text-heavy)10,00015–25 GB
Business site (lead gen)25,00040–70 GB
E-commerce store50,000100–200 GB
Photo/video portfolio50,000150–300 GB
Software downloads5,000200–500 GB

If your calculated bandwidth is within 20% of your plan's limit, you're at risk of an overage during a traffic spike. Either upgrade the plan or offload media to a CDN.

Frequently asked questions

Is "unlimited" bandwidth actually unlimited?
No. It's "unmetered" within a fair-use policy. Most shared hosts will contact you if you consistently exceed 50–100 GB/month, or if your site consumes too much CPU serving files. Read the terms of service — "unlimited" almost always has a soft limit.
How do I measure my actual page size?
Open Chrome DevTools → Network tab → reload the page → look at the bottom of the list for "Transferred" or "Size." That's the actual data sent over the wire. Compressed assets (gzip/brotli) are counted as their compressed size, not the uncompressed size. Do this on 3–4 different pages and average them.
Does a CDN reduce my bandwidth usage?
Yes — significantly. When you serve images, CSS, and JS through a CDN, those files are cached on edge servers. The CDN serves them to visitors, so your origin server only sends the HTML and dynamic content. For image-heavy sites, this can cut origin bandwidth by 60–90%. You pay the CDN instead, but it's often cheaper than upgrading hosting.
What happens if I exceed my bandwidth limit?
Depends on the host. Some charge overage fees ($0.50–$2 per GB over). Some suspend your site until the next billing cycle. Some throttle your speed. Check your host's policy before you hit the limit — the overage fees can be brutal if you're not expecting them.
MU
Mujahid — Runs cPanel, DirectAdmin, and CyberPanel stacks across 50+ client deployments. Every calculator on this site is checked against real server configurations.