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Free Bandwidth Calculator

Plan requirements for ISP Oversubscription. Required Uplink Capacity estimator.

Network Load Parameters

subs
Mbps

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Required Uplink Capacity

2.5 Gbps
Suggested Port: 10G / SFP+

Planning Metrics

Total Sold Bandwidth
25 Gbps
Real Avg Speed / User
5 Mbps
* Assuming peak concurrency matches your specified contention ratio. Real-world usage varies by region and time of day (Netflix Prime Time).

What is ISP Oversubscription?

Oversubscription (or Contention Ratio) is the practice of selling more bandwidth to subscribers than the ISP has available in its core network or upstream connections. This is standard industry practice because not everyone uses their connection at 100% capacity simultaneously.

Recommended Ratios

  • 1:1 (Dedicated): Guaranteed bandwidth. Used for DIA (Dedicated Iternet Access) and mission-critical business lines.
  • 1:10 (Residential): Standard balance for Fiber/GPON networks. Good user experience.
  • 1:20 to 1:50 (Budget): Used for lower-cost residential plans, WISP networks with limited backhaul, or bulk Wi-Fi.