How much bandwidth does a video call use?

It depends on the resolution, frame rate, codec and settings, so there is no single figure. Enter the bitrate you measured for one participant, audio and video together. In Chrome you can read the real bitrate of a call at chrome://webrtc-internals.

Why does a mesh call get expensive so quickly?

In a mesh every participant sends a separate copy of their video to every other participant, so uploads grow with the number of people. With four people each one uploads three streams; with eight, seven. An SFU keeps each person to one upload.

What is the difference between an SFU and an MCU?

An SFU (selective forwarding unit) receives each stream once and forwards it to the others without decoding it, so it uses little processing but sends many streams. An MCU (multipoint control unit) decodes and mixes everyone into a single stream per viewer, which needs much more processing and adds latency but sends one stream to each person.

Why is 1 GB counted as 1,000 MB here?

Transfer allowances and cloud bills count in decimal units, so the calculator does too. If your provider uses 1,024 (gibibytes), the totals are about 7% smaller.

What does the uplink multiplier do?

It applies to the SFU row only. If each participant sends several quality layers of the same video (simulcast), their upload is more than one stream, and the server receives more. Set it from the layers you actually send; 1 means one stream.

Video bandwidth calculator

How much data does a stream move, and how much bandwidth does a video call need for each person and on the server? Enter your own bitrate; the arithmetic is the part people get wrong.

Free · Runs in your browser · Updated 26 September 2026

What are you sizing?

A stream watched by manyData transferred and the bandwidth needed at peak.A video callBandwidth per person and on the server, for mesh, SFU and MCU.

Bitrate

Video plus audio, as delivered to each viewer.

Viewers at once

Everyone watching at the same time.

Hours per viewer

Per viewer: 4.5 GB
All viewers: 450 GBDecimal gigabytes (1 GB = 1,000 MB), as bills and allowances count them.
Peak bandwidth out: 500 MbpsEveryone watching at once.

1 Mbps for one hour is 3,600 megabits, which is 450 megabytes (0.45 GB). The bitrate is what you deliver, so a stream you also record or re-encode moves more.

Streaming

Data transferred is bitrate times time.

Data per viewer

gigabytes = Mbps × 3,600 × hours ÷ 8 ÷ 1,000

One megabit per second for one hour is 3,600 megabits. Divide by 8 for bytes: 450 megabytes, which is 0.45 GB. So a 5 Mbps stream watched for 2 hours moves 5 × 2 × 0.45 = 4.5 GB, and 100 people watching it move 450 GB. The peak bandwidth you must serve is the bitrate times the number of people watching at the same moment: 500 Mbps for those 100.

Calls

The design decides who pays for the bandwidth.

N is the number of participants and b is the bitrate of one stream.

Bandwidth for a video call by design
Design	Each person uploads	Each person downloads	Server receives	Server sends
Mesh	(N − 1) × b	(N − 1) × b	No server	No server
SFU	b (more with layers)	(N − 1) × b	N × b	N × (N − 1) × b
MCU	b	b	N × b	N × b

Mesh needs no media server, which is why it is attractive for two or three people, but each person’s upload grows with every added participant.
SFU caps each person’s upload at one stream and moves the cost to the server, whose outgoing traffic grows with the square of the room size.
MCU is the lightest for each person and the heaviest on the server’s processors, because it decodes and re-encodes every stream.

Limits

Use it for planning, then measure.

The bitrate is yours to supply. Measure it with your codec, resolution and frame rate, ideally from a real call in chrome://webrtc-internals or your provider’s statistics.
The call figures assume everyone is visible at full quality at once, which is the worst case. Real SFUs send smaller versions of streams that are not the focus, so measured numbers are usually lower.
Screen sharing, audio-only participants, retransmissions and packet headers are not modelled. Add margin for them.
When two people cannot connect directly, their media is relayed through a TURN server, which then carries the traffic in both directions. Size the relay separately if many of your users sit behind restrictive networks.

FAQ

Questions people ask first.

How much bandwidth does a video call use?: It depends on the resolution, frame rate, codec and settings, so there is no single figure. Enter the bitrate you measured for one participant, audio and video together. In Chrome you can read the real bitrate of a call at chrome://webrtc-internals.
Why does a mesh call get expensive so quickly?: In a mesh every participant sends a separate copy of their video to every other participant, so uploads grow with the number of people. With four people each one uploads three streams; with eight, seven. An SFU keeps each person to one upload.
What is the difference between an SFU and an MCU?: An SFU (selective forwarding unit) receives each stream once and forwards it to the others without decoding it, so it uses little processing but sends many streams. An MCU (multipoint control unit) decodes and mixes everyone into a single stream per viewer, which needs much more processing and adds latency but sends one stream to each person.
Why is 1 GB counted as 1,000 MB here?: Transfer allowances and cloud bills count in decimal units, so the calculator does too. If your provider uses 1,024 (gibibytes), the totals are about 7% smaller.
What does the uplink multiplier do?: It applies to the SFU row only. If each participant sends several quality layers of the same video (simulcast), their upload is more than one stream, and the server receives more. Set it from the layers you actually send; 1 means one stream.

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Video bandwidth calculator