Bandwidth Calculator
Nobody sizes a link at 100% utilisation.
Work out Bandwidth. Nobody sizes a link at 100% utilisation. Free, with no account and nothing to install.
Link capacity needed
429 Mbps
60 concurrent users · A gigabit link covers this
Real links are not sized at full utilisation. Above roughly 70%, queueing delay rises sharply — that is a result from queueing theory rather than a vendor rule of thumb — so the headroom is an explicit input here rather than a hidden multiplier. Concurrency is where estimates usually go wrong, in both directions. A busy office might see 30% of users generating traffic at once; a video-heavy environment can approach 100% in short bursts and idle almost completely between them. The monthly data figure matters when the link is metered rather than flat-rate. Cloud egress, mobile backhaul and satellite links are all charged by volume, and a comfortably-sized link can still produce an uncomfortable bill.
How the Bandwidth Calculator works
Link capacity for a user count, concurrency and per-user rate, with explicit headroom. Above roughly 70% utilisation queueing delay rises sharply, which is why the headroom is an input rather than a hidden multiplier.
Also known as: how much bandwidth do i need · mbps per user for an office · internet speed for 200 users · network capacity planning
Frequently asked questions
How much bandwidth do I need per user?
Roughly 1 to 2 Mbps for browsing and email, 3 to 5 for video calls, and 5 to 25 for streaming depending on resolution. The concurrency assumption matters more than the per-user figure.
Why leave headroom?
Because queueing delay rises sharply above about 70% utilisation. That is a result from queueing theory rather than a vendor rule, and it is why a link running at 95% feels broken while showing capacity to spare.
What concurrency should I assume?
A busy office might see 30% of users generating traffic at once. Video-heavy environments approach 100% in short bursts and idle almost completely between them, which makes averages misleading.
Does upload matter as much as download?
More than it used to. Video calls, cloud backup and remote desktop are all upload-heavy, and asymmetric connections that look generous on paper often bottleneck on the upstream.
What about the monthly data figure?
It matters when the link is metered — cloud egress, mobile backhaul, satellite. A comfortably-sized link can still produce an uncomfortable bill if the charging is by volume.
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