About the Bandwidth & Data Usage Calculator
This bandwidth calculator estimates two numbers hosting plans and CDNs bill on: how much data you transfer in a month (GB or TB) and how fast your connection or server uplink must be (Mbps). Pick what you are serving — website page views, live or on-demand video streams, or file downloads — and enter your traffic. The tool converts it to monthly transfer, the average bit rate over the month and a recommended peak bandwidth.
Traffic is never spread evenly: most sites see several times their average load in the busiest hour, and launches or viral posts spike far higher. The peak factor adds that headroom for websites and downloads; for streaming, the number of simultaneous viewers already is the peak.
Use it to size a VPS or dedicated server port, compare hosting plans with transfer caps, budget CDN egress costs or check whether an office line can carry a webinar. Figures use decimal units as network providers do: 1 GB = 1,000 MB, 1 Mbps = 1,000,000 bits per second, and a 30-day month.
With the default inputs, the recommended bandwidth is 3.47 Mbps. Change any value above to recalculate instantly.
How to use the bandwidth & data usage calculator
- 1Choose website, streaming or downloads.
- 2Enter monthly visitors and page weight, viewers and bitrate, or downloads and file size.
- 3Set a peak factor for how much busier your busiest hour is than average.
- 4Read the recommended Mbps and monthly transfer, then compare hosting or CDN plans.
Formula and method
Monthly transfer is the number of requests multiplied by the size of each one: visitors × pages per visit × average page weight for a website, or downloads × file size. Converting to an average rate multiplies megabytes by 8 to get megabits and divides by the 2,592,000 seconds in a 30-day month. Because real traffic bunches into busy hours, the average is multiplied by a peak factor (3× is a sensible default; use more for launches or spiky traffic).
For streaming, the required bandwidth is simultaneous viewers × stream bitrate, since each viewer gets a separate stream. Monthly data is that rate × 3,600 seconds × hours per day × 30 days, divided by 8 to convert bits to bytes. All units are decimal (1 GB = 1,000 MB, 1 TB = 1,000 GB), matching how ISPs and hosts measure bandwidth.
- MB
- Megabytes transferred per month
- Mbps
- Megabits per second
- peak factor
- Busiest-hour traffic ÷ average traffic
Worked examples
Small business website
50,000 visitors × 3 pages × 2.5 MB = 375,000 MB = 375 GB a month. Spread over 2,592,000 seconds that averages 375,000 × 8 ÷ 2,592,000 ≈ 1.16 Mbps; with a 3× peak factor you need about 3.5 Mbps.
1080p live stream to 100 viewers
100 viewers × 5 Mbps = 500 Mbps of upload while live. Four hours a day for 30 days is 500 × 3,600 × 4 × 30 ÷ 8 = 27,000,000 MB = 27 TB a month.
Software downloads
10,000 downloads × 150 MB = 1,500 GB (1.5 TB) a month, an average of 1,500,000 × 8 ÷ 2,592,000 ≈ 4.63 Mbps. Release days are spiky, so a 4× peak factor suggests about 18.5 Mbps.
Frequently asked questions
What is the difference between bandwidth and data transfer?+
Bandwidth is a rate — how many megabits per second a connection can carry. Data transfer is a volume — how many gigabytes moved in a month. Hosts often call monthly transfer “bandwidth”, but a plan with 1 TB of transfer and a 100 Mbps port describes both limits.
How do I find my average page size?+
Open your browser’s developer tools, go to the Network tab, reload the page with the cache disabled and read the total transferred at the bottom. Image-heavy pages often weigh several megabytes, while repeat visitors download less because cached files are reused — so a first-visit measurement is a safe upper estimate.
How much bandwidth does video streaming use?+
Roughly 1.5 Mbps for 480p, 3 Mbps for 720p, 5 Mbps for 1080p and 15–25 Mbps for 4K, which is about 0.7, 1.4, 2.3 and 7–11 GB per hour respectively. Each viewer needs their own stream.
Why are Mbps and MB/s different?+
Network speeds use bits and file sizes use bytes, and 1 byte is 8 bits. A 100 Mbps link moves at most 12.5 MB per second — in practice a little less because of protocol overhead.
What peak factor should I use?+
For steady traffic 2–3× is typical; for sites with a strong daily rhythm, marketing emails or product launches use 5–10×. If you serve through a CDN, the origin server needs far less because most requests are answered from cache.