Bandwidth Planning Calculator

How it works

Estimate how many devices will be busy at the same time, then enter the average throughput each will need in the same direction. Multiply these to obtain simultaneous demand. The extra-capacity percentage is added on top of that demand. For example, 25% extra capacity means multiplying demand by 1.25; it does not mean reserving 25% of the final connection unused.

Use separate calculations for download and upload. A connection with adequate download capacity may still struggle with simultaneous video calls, cloud backups or file uploads when its upstream capacity is lower. Include only simultaneously active devices rather than every device connected to the router. For very different workloads, add their expected demands yourself and use one device with that combined Mbps value.

This is an arithmetic planning aid. It cannot determine an internet plan’s real performance or guarantee that Wi-Fi will deliver the planned throughput. Radio conditions, access-point placement, local cabling, latency, packet loss, router performance and service congestion also matter. The default per-device demand and extra allowance are examples you can change, not a published requirement for a particular app. Check the applications you actually use and allow additional capacity for uncertainty.

A worked example

Four simultaneous devices × 10 Mbps = 40 Mbps of estimated demand. Adding 25% gives 50 Mbps of planned capacity. Run the same calculation with your upload workloads to plan upstream capacity.

Common questions