How Much Bandwidth is Needed for VoIP?

VoIP bandwidth is measured in kilobits per second (kbps). It refers to the amount of data (voice) sent or received every second. To ensure superior calls, you need to calculate the bandwidth based on your chosen codec and the number of simultaneous calls and add a buffer for overhead.

Different codecs consume varying amounts of bandwidth. Here are some standard codecs and their approximate bandwidth requirements:
 

• G.711: About 87.2  kbps for each call.
• G.729: About 31.2 kbps for each call.
• G.722: About 64 kbps for each call.

Decide how many calls you will be making at the same time. For example, if you expect to have 5 simultaneous calls, you must include the number in your calculation.

Multiply the bandwidth requirement of the codec by the number of simultaneous calls.

Example Calculation:

1. Using G.711 Codec:

• Bandwidth per call: 87 kbps
• Number of calls: 5
• Total bandwidth required: 87 kbps×5= 435 kbps (0.435 Mbps)
   

2. Using G.729 Codec:

• Bandwidth per call: 31.2 kbps
• Number of calls: 5
• Total bandwidth required: 31.2 kbps×5= 156 kbps (0.156 Mbps)

Adding around 20% more bandwidth to account for network overhead and ensure quality is a good practice.
For the G.711 example:
 

• Total with overhead: 435 kbps×1.2= 522 kbps (0.522 Mbps)

Additional Note
Always check your internet plan to make sure you have enough bandwidth available for your VoIP needs, especially if other devices or applications are also using the internet simultaneously.

VoIP requires bandwidth of at least 80-100 kbps (or less) for a single call. However, more bandwidth is required for multiple users. The more users, the more bandwidth is required. VoIP Bandwidth requirements also depend on the codec. A codec compresses and decompresses voice data during a call.
 

• G.711 codec: It requires around  80 Kbps (64 Kbps voice + 16 Kbps overhead) per call. This is high-quality but uses more bandwidth.
• G.729 codec: It uses about 32 kbps per call. It’s more efficient and uses less bandwidth.

The number of simultaneous calls, type of codec, network congestion, jitter, and packet loss are some factors that affect VoIP bandwidth.

The more calls that happen at the same time, the more bandwidth you’ll need. Each call takes a specific amount of data, so if you have multiple calls happening, the data adds up.

For example, if each call uses 100 kbps, five simultaneous calls require 500 kbps bandwidth. Not having enough bandwidth can cause poor call quality, delays, or dropped calls.

A codec program compresses and decompresses voice data for VoIP calls. Different codecs use different amounts of bandwidth. For example:
 

• G.711 codec offers high call quality but uses more bandwidth (80 Kbps (64 Kbps voice + 16 Kbps overhead)).
• G.729 codec uses less bandwidth (about 8-32 kbps per call), which is better for saving bandwidth, but the call quality may not be as high.

Jitter or packet loss occurs when some voice packets fail to reach their destination, resulting in gaps or silences during a VoIP call. Delays, distortions, or missing audio occur when there is jitter or packet loss in VoIP calls.

Congestion occurs when too much data flows over a network simultaneously, causing slowdowns and reduced quality. Any delays resulting from congestion can disrupt the flow of voice data, resulting in distorted or delayed audio, making it difficult for users to talk clearly.

If other activities, like video streaming, large downloads, or online gaming, are happening at the same time as your VoIP calls, they will compete for the same bandwidth. This can slow down your VoIP calls, making the audio choppy or delayed.

You can optimize VoIP bandwidth frequency by reducing the number of simultaneous calls, using more efficient codecs, improving network quality to minimize jitter and packet loss, and managing network congestion with Quality of Service (QoS) settings.

Select a codec that uses less bandwidth without compromising quality. For example, the G.729 codec compresses voice data more efficiently, reducing bandwidth use while providing decent audio quality.

To ensure clear calls, avoid streaming videos, downloading large files, or playing online games while making VoIP calls. These activities consume a lot of bandwidth and can interfere with the quality of your VoIP service. If possible, schedule heavy internet usage when you are not on calls.

QoS is a feature in most routers that prioritizes certain types of traffic over others. By configuring QoS settings to prioritize VoIP traffic, you can ensure that your VoIP calls receive more bandwidth than other types of internet use.

If your internet connection frequently struggles with bandwidth, consider upgrading your plan. A higher bandwidth plan will allow more simultaneous calls and other internet activities without sacrificing call quality.

VoIP needs at least 100 kbps for one call, but its bandwidth requirements increase with more calls and vary by codec. For example, G.711 needs around 87 kbps, while G.729 requires only 31 kbps. To keep call quality high, add about 20% extra bandwidth for overhead. If your phone calls are choppy or dropping, upgrading to a higher-bandwidth plan can improve VoIP reliability, ensuring clear, uninterrupted communication that supports your business needs.

Choose a reliable VoIP phone service provider like Calilio. It offers excellent call quality integrated with AI features that can impact your business growth. If you have any queries about switching your PBX to a VoIP system, contact us now!

A bandwidth of 100 kbps is required for a single VoIP call. If you have multiple users, you’ll need more bandwidth, depending on the number of simultaneous calls and the codec used.

Different codecs use different amounts of bandwidth. For example, the G.711 codec uses about 87 kbps, while the G.729 codec uses around 31 kbps per call.

If you don’t have enough bandwidth, you may experience poor call quality, such as choppy audio, delays, or dropped calls.

You can improve call quality by choosing an efficient codec, limiting other internet activities during calls, using Quality of Service (QoS) settings, and ensuring you have sufficient bandwidth.