VoIP stands for Voice over Internet Protocol, and refers to a bundle of technologies that enable voice communication over the internet. Compared to landlines, VoIP is generally more cost-effective and flexible. All you need is an internet connection, a device that connects to the internet, and you can make calls to and from anywhere in the world.
The truth is, you don’t need a lot of bandwidth to use VoIP, certainly not by today’s standards — but there are usually a lot of other apps and services competing for that bandwidth. Any delays or issues with the transmission, and callers will notice it immediately.
In a busy office with users on CRM software and downloading large files, it’s important to make sure that VoIP calls continue to get priority for bandwidth. If not, you could experience choppy, low-quality calls even though you have, in theory, plenty of bandwidth to support VoIP.
If you are having trouble getting clear calls right now, check out our list of VoIP troubleshooting tips. Most fixes only take a few minutes.
Featured Partners
How much bandwidth does VoIP require?
Generally speaking, you can get decent call quality anywhere in the 60-100 Kbps range, depending on your VoIP provider or business phone service.
Okay, let’s back up and explain exactly what that means.
Internet bandwidth refers to the amount of data you can transmit in a given amount of time. Most often, internet bandwidth is measured in megabits per second (Mbps).
The more bandwidth you have, the more data you can transfer at once, and the faster your internet connection will be.
So, how much bandwidth do you need for VoIP? Well, it depends on a few factors such as the number of simultaneous calls you want to make, the audio quality you desire, and whether or not you’re using other applications that require internet bandwidth at the same time.
As a general rule, one high-quality VoIP call generally requires at least 100 kilobits per second (Kbps). This means that five simultaneous calls require 500 Kbps, 10 calls require 1,000 Kbps, and so on.
Keep in mind that these requirements are valid for very high-quality audio — but you can make do with much less bandwidth and still get good call quality. For example, you could try a different VoIP codec that provides clear calls over slower internet connections rather than the highest possible audio quality.
Upload and download speeds for VoIP
Your bandwidth upload speed is the rate at which you can transmit data from your device or network to another device connected to the internet. Your bandwidth download speed is the rate at which you can retrieve data from websites or servers.
If you want a smooth VoIP experience, you need sufficient bandwidth, particularly if multiple people in the same team are making phone calls at the same time. If your upload speed is too low, you won’t be able to make calls, and if your download speed is too low, you might have issues with the call quality.
That being said, most high-speed internet connections today will provide you with more than enough bandwidth. Here are the most common types of internet connections and what you need to know about each of them.
- DSL: DSL (Digital Subscriber Line) uses a landline telephone network to transmit digital data. It can reach speeds up to 100 Mbps, though you’re more likely to see speeds in the range of 5-35 Mbps for downloads and 1-10 Mbps for uploads.
- Cable internet: Cable internet is a solid option if you want to make phone calls online. It can reach speeds of up to 1,000 Mbps. Average speed ranges are 25-500 Mbps for downloads and 5-50 Mbps for uploads.
- Fiber optic: Fiber optic internet is the fastest type of connection you can get. It can reach staggering speeds that go beyond 1,000 Mbps, and it also offers a relatively symmetrical upload and download bandwidth. Average ranges for both uploads and downloads range from 250 to 1,000 Mbps.
- Satellite internet: The main advantage of satellite internet is that it can be used in remote areas, such as in the mountains or small towns where cable internet may not be available. For satellite internet, the average download speed ranges from 12-100 Mbps, and the average upload speed ranges from 3-20 Mbps.
All in all, if you run a busy office, fiber internet is your best option. It offers the highest speeds, and upload/download speeds are the same.
Keep in mind that whatever your Internet Service Provider (ISP) advertises or bills as their internet speed is likely not the actual speed. They usually advertise an ideal maximum, but realistically, your bandwidth will be much lower. Learn more about how to select the right ISP for your situation.
VoIP bandwidth requirements aren’t usually the issue
While you need a decently fast internet connection to make VoIP calls, stability matters more than bandwidth most of the time. This is one of the most important things to know about VoIP: a stable connection is required for clear calls.
The reason is that small delays or issues with transmission will cause noticeable problems for callers. Someone downloading a file won’t care if it’s a few seconds late — trying to have a conversation with delays and phone echoing is horrible.
So, even with plenty of bandwidth, an unstable connection can lead to poor call quality. This is often often caused by issues such as:
- Jitter: This VoIP issue refers to the variation between packet delays for voice communications. You’ll notice this problem when one party sounds clear, but the other does not—and it’s more often than not associated with a somewhat unstable internet connection. Network congestion and poor-quality hardware can also contribute.
- Packet loss: Packet loss happens when part of the transmitted data fails to reach its destination, often due to an unstable internet connection or network congestion. This issue will frequently manifest as calls that break up so you can only hear part of what the other party says.
- Echo: Although less disruptive, echo is a relatively common issue in VoIP calls. When an echo occurs, you will hear your own voice coming from the other end of the call. This problem is not always related to the quality of the internet connection, as other factors can come into play. Audio settings, headsets, and hardware issues can all contribute to echo.
- Latency: Latency is the delay between the moment data is sent to your phone or laptop and the moment you can hear it in your headphones. To some, latency might sound a lot like audio delay or echoes, so this issue tends to be associated with internet connections. However, that isn’t always the case, as latency is commonly caused by device software updates, improperly plugged headphones, network issues, or congested networks.
These are some of the more common issues users associate with VoIP communication. Some of them can be annoying and downright disruptive, but the good news is that there are a lot of tactics to address packet loss, network jitter, and other common issues.
For instance, if your VoIP system doesn’t already have one built in, you can install a jitter buffer, which is a small software application that reduces the amount of jitter in your calls. This quick fix can help you avoid delays and improve your overall sound quality.
Likewise, you can configure Quality of Service (QoS) settings to re-prioritize the traffic in your local network. Normally, this takes less than a few minutes to do, but it improves audio quality and reduces packet loss.
Other VoIP fixes include:
- If your device has a recommended headset, try to use that one, as it can potentially improve sound quality and reduce echo. Any good VoIP headset should work fine.
- Purchase a newer router designed for VoIP if yours is a few years old, as it will have the latest technology and likely better range.
- Segment your VoIP phones into their own virtual local area network (VLAN), as this helps you improve your VoIP performance and security.
- Switch from Wi-Fi to ethernet, as it usually allows for a much higher and more stable internet speed.
