How much bandwidth do I need for X simultaneous VoIP calls?
Rule of thumb: G.711 takes around 90 kbps per call with overhead, Opus around 40 kbps. But peak burst and headroom for other data count, so plan generously.
Try this first
- 1Estimate peak simultaneous calls (peak, not average).
- 2Multiply calls by 100 kbps (G.711) or 50 kbps (Opus) as baseline.
- 3Double for headroom, VoIP shares the path with other apps.
- 4On limited upload (ADSL, weak 4G): choose Opus or cap simultaneous calls in the PBX.
When to bring us in
Symmetric 50/50 or better helps, asymmetric 200/20 is a risk for more than 5 simultaneous calls.
See also
- Voys, BelXS or RoutIT, which cloud PBX fits?Three popular NL platforms, differences are admin UI, partner model and per-user price.
- Teams Phone: Calling Plan, Direct Routing or Operator Connect?Three ways to connect PSTN to Teams, cost and management differ a lot.
- 3CX: self-host on VPS or take 3CX cloud?Self-host saves licence, but you own SBC, backup and updates.
None of the above fits?
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