Hong Life CalculatorsUnderstanding the website bandwidth calculator — concept and principle
Hosting plans and servers are sized by how much data your site sends. This calculator estimates monthly data transfer from page views and average page size, converts it into average and peak bandwidth in megabits per second, and adds a safety margin so you can choose a plan or server connection with room to grow.
How it is calculated
Monthly transfer (GB) = page views × page size (MB) ÷ 1,000
Average bandwidth (Mbps) = GB × 8,000 ÷ (days × 86,400)
Peak bandwidth = average × peak-to-average ratio
Bandwidth to plan for = peak × (1 + margin ÷ 100)
Page views per second = page views ÷ (days × 86,400)
- Decimal units: 1 GB = 1,000 MB, 1 byte = 8 bits.
The principle
Every page view downloads the page's HTML, images, scripts, styles and fonts. Multiplying views by the average page weight gives the monthly volume. Spreading that volume over all the seconds in a month gives an average rate, but real traffic is uneven: evenings, weekdays and promotions bring peaks several times the average. A server or connection must handle the peaks, not just the average, so the calculator multiplies by a peak ratio and then adds a margin for growth and bursts.
Worked example
Default inputs: 300,000 page views, 2.3 MB per page, 30 days, peak 3× average, 25% margin.
- Transfer = 300,000 × 2.3 ÷ 1,000 = 690 GB per month (23 GB per day); with margin 862.5 GB.
- Seconds in the month = 30 × 86,400 = 2,592,000.
- Average = 690 × 8,000 ÷ 2,592,000 = 2.13 Mbps; peak = × 3 = 6.39 Mbps.
- Bandwidth to plan for = 6.39 × 1.25 = 7.99 Mbps.
- Page views per second: 0.116 average, 0.347 at peak.
| Page views per month | Bandwidth to plan for (Mbps) |
|---|---|
| 75,000 | 2 |
| 150,000 | 3.99 |
| 225,000 | 5.99 |
| 300,000 | 7.99 |
| 375,000 | 9.98 |
| 450,000 | 11.98 |
| 600,000 | 15.97 |
How to read the result
The 2.3 MB default is close to the HTTP Archive's 2024 median mobile page weight. Browser caching and a content delivery network (CDN) reduce what your own server sends, so the transfer billed by your host can be much lower than this estimate. If your plan meters monthly transfer, compare the GB figure; if it limits connection speed, compare the Mbps figure. Optimising images often cuts page weight more than anything else.
Common mistakes
- Using only the HTML size instead of the whole page weight.
- Planning for the average instead of the peak.
- Mixing megabytes (MB) and megabits (Mb).
- Forgetting traffic from bots and API calls.
Frequently asked questions
What is the difference between MB and Mb?
A megabyte is 8 megabits; bandwidth is usually given in megabits per second.
How big is a typical web page?
The HTTP Archive's 2024 median was about 2.3 MB on mobile and 2.7 MB on desktop.
How does a CDN help?
It serves cached files from servers near visitors, reducing your origin server's transfer.
What peak ratio should I use?
Look at your hourly analytics and divide the busiest hour by the average hour; campaigns can spike much higher.
Sources: HTTP Archive, Web Almanac 2024, "Page Weight" chapter · BIPM SI Brochure, 9th edition (decimal prefixes); IEC 80000-13 (1 byte = 8 bits)