Bandwidth Calculator
Monthly transfer and peak Mbps for a website or video stream.
About this tool
For a website, enter the average page weight, monthly page views, traffic pattern, headroom and how much a CDN cache offloads. For streaming, choose the quality, peak concurrent viewers and total hours watched. You get monthly transfer and average and peak throughput.
How bandwidth is estimated
Hosting plans and CDNs charge or cap by data transfer (GB or TB per month), while servers and connections are limited by throughput (megabits per second). For a website, monthly transfer is average page weight × page views: a 2.2 MB page viewed 150,000 times is 330 GB, or about 429 GB with 30% headroom for growth, bots and spikes. Average throughput spreads that over the month, but real traffic bunches into busy hours, so the peak is commonly 3–10 times the average depending on whether your audience is steady, office-hours or driven by campaigns. A CDN serving cached images, scripts and styles means your origin server only sends what isn't cached. For streaming, peak bandwidth is bitrate × concurrent viewers: 200 viewers at 1080p (about 5 Mbps) need around 1 Gbps. Monthly transfer is bitrate × total hours watched, so 12,000 hours at 5 Mbps is 27 TB. Honest limits: measure real page weight in your browser's DevTools Network tab (returning visitors download less thanks to caching). Providers count GB differently (1,000 or 1,024 MB), and adaptive streaming varies bitrate with each viewer's connection. The download time calculator, the video file size calculator and the unit converter are related.
Frequently asked questions
How much bandwidth does my website need?
Multiply average page weight by monthly page views, then add 25–50% headroom. 2 MB × 100,000 views ≈ 200 GB.
What is the difference between bandwidth and data transfer?
Data transfer is the total amount moved per month (GB). Bandwidth is the rate at any moment (Mbps).
How much bandwidth does streaming use?
Roughly bitrate × viewers: about 5 Mbps per 1080p viewer, so 100 viewers need about 500 Mbps.
Is anything stored or sent?
No. Everything is generated in your browser and nothing is stored or sent.