Bandwidth Calculator

Work out the connection speed a transfer needs, how much monthly bandwidth a website uses, or how a hosting plan's GB per month compares with Mbps. The bandwidth calculator handles bits and bytes for you.

Updated
Runs in your browser. Your data is not uploaded.
Calculate

1.5 leaves room for traffic peaks and bots.

Convert

Bandwidth needed
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How to use the Bandwidth Calculator

  1. Under Calculate, pick Data rate (speed for a data volume), Website (monthly site bandwidth), or Hosting (GB per month vs Mbps).
  2. Fill in the fields for that mode, such as Amount of data and Every, or Page views per month and Average page size.
  3. Press Calculate. The main figure comes first, with the same result in other units underneath.

How it works

Everything is converted to bits per second (1 byte = 8 bits). KB, MB, GB, and TB are powers of 1,000; KiB, MiB, GiB, and TiB are powers of 1,024. A month is 30 days (2,592,000 seconds).

  • Data rate = data in bytes × 8 ÷ seconds in the period.
  • Website = page views × average page size × redundancy factor. The average speed is that monthly total × 8 ÷ 2,592,000.
  • Hosting, transfer to speed = transfer × 8 ÷ 2,592,000, and speed to transfer reverses it.

The redundancy factor, 1.5 by default, adds headroom for traffic peaks, crawlers, and repeat visits whose cache has expired.

Examples

  • 10 GB per hour needs 22.22 Mbps sustained.
  • 100,000 page views a month at 2 MB each with a factor of 1.5 = 300 GB per month, an average of 0.93 Mbps.
  • 1 TB per month of hosting transfer = 3.09 Mbps sustained.
  • A 100 Mbps port used around the clock moves 32.4 TB in 30 days.

Limitations

  • Results are averages. Real traffic peaks in busy hours, so size a connection for the peak, not the monthly average.
  • Protocol overhead is not included. Add 10 to 20% for TCP/IP headers and retransmissions.
  • Hosts measure months differently. Some bill 95th-percentile usage instead of total transfer, which this tool does not model.

Frequently asked questions

How much bandwidth does my website need?

Multiply monthly page views by the average page size, then by about 1.5 for headroom. 50,000 views of a 3 MB page need about 225 GB a month.

How many GB per month is 1 Mbps?

About 324 GB in a 30-day month if the line is used at full speed all the time: 1,000,000 bits × 2,592,000 seconds ÷ 8.

What is the difference between bandwidth and data transfer?

Bandwidth is a rate, such as 100 Mbps: how much can move per second. Data transfer is a volume, such as 500 GB: how much actually moved over a period. Hosting plans often call the monthly volume "bandwidth".

Often used together with the Bandwidth Calculator.